Hell if I know, I recall some discussion involving grub no-splash but maybe I’m conflating the forum posts I read. The main idea is that some process is running and preventing the graceful shutdown but I haven’t read the posts in a while.

I do find it odd this only happened after a reinstall where grub is realistically the only change (shifting the install drive + boot options, deleting windows)

I know I gotta do some digging if I want to fix it but I’ve got other fish I’d rather fry