Let’s try to attract some extra attention to this. @philm
In the meantime, please post output from these commands; they will likely be useful for reference:
inxi --admin --verbosity=7 --filter --no-host --width
journalctl --boot=-1 --priority=3 --catalog --no-pager
I understand they may be busy at the moment, but I’m sure someone from the Team will look at this as soon as they are able.
Thanks for reporting this. Cheers.
Update:- I found this related Arch thread Cannot Shutdown/poweroff with AMD Radeon 7800 XT. Certainly the issue isn’t uncommon for this card; and I noticed a similar mention in comments of Unstable Update December 2023, so I imagine the Team is aware of it.