Months ago after i decided to get a new SDcard with less GBS, i didn't want to go through reconfiguring my raspberry pi with arch linux, so i tried 2 things:
A) Make a backup using rsync so i could just copy all files over to the new sdcard -> Half worked.
B) Copy over using spacefm, just like regular files -> Didn't work
With option A i was able to boot and it was perfect, but i didn't had any programs (according to pacman) so i decided to reinstall everything that was installed before. It worked and it took like 1 hour to get everything up again.
In the end, my raspberry had a kernel update and it just ..corrupted the sdcard after a clean legit reboot.
Don't be lazy, make a new sdcard img, it will save you the trouble of having to reinstall everything later.