@Libhero Yes this does seem like another sign that the Framework USB problems are power related (assuming your sticks work fine in another computer).
To review the evidence:
USB 2.x connections work fine. It’s the USB 3.x connections that have a problem. If I force a problematic device to connect via USB 2.x either by using a USB 2.x speed cable or by doing the halfway plugin trick, the problems go away.
(The halfway plugin trick doesn’t work for all USB-A devices, though, so the only way I know to guarantee a USB 2.x connection is to use a USB extender cable or dongle that’s only rated for USB 2.x speeds.)
If I use a powered USB-C hub, the problems go away. If I don’t power the powered USB-C hub, the problems come back.
Evidence of other people with the problem:
Unfortunately, this 1 TB drive disconnect megathread was closed before I figured out the USB 3 vs 2 angle so I wasn’t able to ask people to try it. I guess I could create a new thread that’s like “Hey everybody with framework storage expansion card disconnect problems, try forcing them to connect at USB 2 speeds.” And maybe even give a link to this cheap USB 2 speed dongle to test with. And a link to the powered hub for those who are willing to pay more for the test. The hub is useful, though, and even has a 1 Gbps ethernet port.