Not really, I know more about the underlying technologies than about the products actually using them XD.
The mentioned Plugable should be able to do what you want. I personally would not want it, because it limits the DP bandwidth so it can reliable give you 2 DP connections tunneled through USB4 at HBR2 speeds and there is no way to get a DP connection not interfered with by MST out of it or a TB-out. It also forces conversion to HDMI for 2 of its outputs. But all of that does not limit your specific use case.
Most widespread docks (Lenovo, HP, Dell) only have 3 ports driven by MST and drive all of them only via a single DP connection (but a faster one than the Plugable). If they have TB-outs in addition to the MST-Ports, 1 of them can be used for a 4th monitor, as long as that stays below HBR1 bandwidth (like your FHD and below monitor definitely do). So they basically just distribute the bandwidth unevenly across the 2 DP connections inside USB4 to have the 3 main ports also work over non-TB/USB4 and to allow higher resolutions (like 8K). In this class, I like the Dell WD22TB4 for its 2 TB outs (because right now, there is only a single Intel TB controller and it has 3 outputs, so it is very cheap and stupid of docks using that controller not giving you access to at least 2 of them directly).
The only big dock with 4 MST-based monitor outputs I know is the Lenovo TB4 dock, but that still has a weird topology internally. And Lenovo does not give (reliable) access to TB-outs as a tradeoff.
Technically one can chain MST-Hubs and get to what the Lenovo Dock does internally with additional, external MST-Hubs, or one integrated into monitors, but mixing and matching them makes calculating the bandwidth capabilities much more difficult.
Whether you get problems, with some monitors not waking up from sleep or such, is highly dependent on your exact setup (monitors, MST-Hubs, topology, adapters). The mor complicated the topology is, the more likely issues are, but you can never be sure without trying.
For example I have 2 Dell WD19TB for my 12th Gen and on one setup, 2 of 3 monitors have trouble waking up, whereas the other setup with bigger monitors does not have that problem (and I am complicating both those setups by using a chained MST-Hub inside a monitor as well).
But I am pretty sure all of them would work easily for your current monitors, because you are at a very low end of bandwidth consumption. But if you upgrade monitors all of them will run into different, complicated to understand, bandwidth limits that one then needs to work around.
So I would recommend just choosing the dock based on its other properties (power, TB-outs, USB ports, LAN Port speed, etc). And prepare yourself for potentially having to try multiple to find a setup where all 4 monitors turn on absolutely reliably (maybe even switching around which port is used for which monitor will do the trick).
wow
well, out of curiosity, what would be the ideal setup for hooking up 4 monitors to the thunderbolt output?
would daisy-chaining the monitors work better?
My reservations about the Plugable dock were solely about the ports (HDMI) and the topology that limits how much bandwidth you can get out of a single port.
Both will probably not impact your setup. DP-HDMI conversion only gets troublesome when you get to the limits of bandwidth, audio or exotic resolutions (non-TV resolutions).
Since DP is what is tunneled through TB, connecting each display with DP makes things less complicated. But if some of your monitors do not even have DP than you do not have a choice with that anyway.
The Plugable way of using 2 HBR2 connections each split with MST+DSC into 2 ports is probably simpler and more predictable for 4x roughly the same resolution monitor.
Chaining monitors with MST is possible, if they have that feature built-in. Then you would not need a Dock with 4 outputs, but less. But on the other hand it will most likely give you a more varied topology that can be harder to predict (the 2 MST hubs are likely not identical and have never been tested in that combination, both tuneled through TB.
Where did you find out that it’s HBR2? That thing is almost 300$ and is using ancient DP tech?
In that case you’d rather get something with 2 propper dp1.4 ports and put a HBR3 capable mst hub on there. In case of op the bandwidth os managable but for that price I’d feel cheated getting hbr2, I have some hbr2 hubs that cost like 20 bucks.
Because that would be pretty much the only way without hacking, to get 2 equally fast DP connections through TB/USB4. If one DP connection is 4xHBR3, there is no longer enough for a 2nd 4xHBR3 connection or even a 4xHBR2 connection.
To reach the numbers Plugable advertised AND still support 2 monitors on Mac that is basically the only way.
That limitation is why on docks like the WD22TB4 you can only get a 4xHBR1 connection on the TB-outs (under normal circumstances), because the integrated MST-Hub will always reserve a 4xHBR3 connection when possible.
(we have a thread on here where we tried to collect a bunch of details about the internal stuff of TB / USB4: Details about USB, Thunderbolt and dock operation)
Edit:
Plugables FAQs said some things that were contradicting me, but the teardown of the dock (Plugable TBT4-UDZ Dock Review and Teardown – Dan S. Charlton) actually proves me right and shows that Plugables FAQs what the dock should be able to do on DP Alt Mode hosts are just wrong. Boy, do I not trust that brand.
Damn those are some fancy mst hubs.
Hell easiest might be to just use 2 usb-c ports and put a club3d 3 port mst hub in one (for 3 of the displays) and a simpler dock in the other (for power usb and the remaining display)
I think you should take a look at Anker 777 Thunderbolt Docking Station (Apex, 12-in-1, Thunderbolt 4).
(sorry to chime in like this, but I dont trust much usb hubs nowadays as I have had bad experience in the past with some of them and stick to good brands now)
It will be the most predictable for sure, as TB limits do not come into play.
But OP is far away from those limits anyway.
That is why in general, I really like the WD22TB4. It gives you a good MST-Hub, but it also gives you 2 TB-outs that you can use instead just like on a TB4 hub. There you can access the raw DP signal, get Adaptive Sync and plug in your own MST-hubs if needed, in case the built-in one does not work for your situation. So just the most flexible option for most use cases.
How is that going to help? It forces conversion to HDMI and only gives you a single TB-out that you’d have to split yourself using an external MST-Hub to get to 4 displays.
In general, I would never recommend going with such a device. Because it is basically a TB4 hub (like CalDigit Element Hub with its 3 native TB-Outs that are most flexible). It is just that 2 USB-C-to-HDMI Adapters are built-in that you cannot get around. Should they not work for your displays, the whole dock is scrap. I am never a fan of the dock manufacturer not exposing ports the TB-controller inside it has, because it just takes your options away. Similar to how the Plugable TBT4-UDZ has the same TB controller with 3 TB outputs, of which 2 are used for each pair of HDMI+DP and the 3rd one is not exposed anywhere, even though you are paying for the controller that has it.
The Lenovo and HP TB4 docks do it the same way. They use the same controller, with 3 TB-outs, but only expose 1 of them. The 3rd one is just wasted, probably because they did not want to rework the existing case to fit an additional port.
True, With a bit of tweaking it could probably all fit into one HBR2 port but I don’t see him using ancient stuff like that sub 1080p screen forever.
Lol that’s the one I have at work, works mostly fine except for it getting confused every few weeks and resetting my keyboard every few seconds.
I kinda hate that hdmi is even still a thing.
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As I realize I have no idea about this stuff and I haven’t contributed anything I’ll leave it to the experts. Sorry for the noise! 
Jul 3, 2023 update
finally got this installed and it seems to work pretty good.
Yes theres a 4 monitor limit.
If i try to turn 5 monitors on, another will turn off.
Curious: Is this an intel chipset limitation or something?
Also, if i buy one of those cheap USB2VIDEO connectors, will that allow me to have 5 monitors?
Yes Intel iGPUs from 11th gen on have increased the monitor limit to 4 from the previous three. More would require an additional GPU.
Nvidia GeForce has the same limit. AMD iGPUs as well. Some AMD dGPUs support more, but seems quite undocumented and depends on very deep internals of the GPU to go above 4…
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what if i buy one of these
Yes. Basically very weak and incapable external GPUs.
Will get you over that limit, but performance is not comparable to native outputs, but might be good enough for simple office use, or people who are not very sensitive to various artifacts etc.
Also requires drivers to work, because it has to pawn off computation to the CPU or iGPU.
Often problematic to get to work under Linux or on devices without administrative privileges.
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That is not a gpu. It will give you an HDMI port for 1 of the 4 displays, but will not expand beyond 4.
If it also works over USB-A, then it cannot be a DP Adapter and must be DisplayLink or similar…
Yes, you’re right. So it would expand beyond the 4 GPU monitors, at the expense of CPU load and performance and needing software drivers.
so the above plugable usb will allow me to get past the 4 monitor rule?
i dont play games - i just need it for MS Office stuff
Yes. That limit is for the iGPU. Different GPU, new limit. Same with a full eGPU.
And for truly static content with only mouse movement, it would probably not be noticable. Only modern office is quite animated from the cursor moving between letters and all the menus. So the difference can likely be perceived in those instances already.
But it all depends on your sensitivity to those things.
If you need to go over 4 monitors, you do not have another choice, other than a much more expensive eGPU. People should just now what they are paying for and absolutely be discouraged from being stuff like that, if there is a choice / the iGPU can still drive more and you have the ports to do so…