I also confirm that the Framework 16 is, so far, unreliable when it comes to suspend:
- s2idle feels like a technological regression compared to S3. I understand Framework is not to blame for this first point though.
- I have seen it failing to suspend, with at least one stacktrace related to the amdgpu driver.
- I have seen it suspending then waking too early while transported in a backpack.
- I have just seen it not waking at all (possibly freezing?) after suspend (I had to long-press the power button to shut it down).
That being said, I cannot complain too much for I do not use an officially supported kernel (I use Debian Sid and its 6.7.9 packaged kernel instead of Ubuntu 22.04).
The elements above were harvested as part of my normal, regular use of the laptop, but I will try to experiment in a more rational way with better logging and tooling, as suggested by Mario.