Under current kernels (6.17) it seems there is an issue with the webcam driver, https://bugzilla.kernel.org/show_bug.cgi?id=220702 . looks like there are still some issues with sleep/webcam at this time, they might be fixed by the 6.18 release.

I got sleep working by disabling webcam in the bios for now.

Well shucks, my sleep was still broken after disabling that :/. Will have to keep poking at it - thanks!