These older (maybe also current) amd gpus for some reason defaults to higher vram speeds when a monitor has mor than 60hz. The fix requires generating a custom edid file, which is a great pain in the ass to get to work

Most distros don’t offer it as an option when installing afaik due to licensing, while btrfs is usually an option along side ext4

Why? I have used btrfs for years and haven’t had any issues with it, it functionally works about the same as ext4.