Nice. This is one of the main reasons why I picked CachyOS recently. Now I can fallback to Ubuntu if CachyOS gets me stuck somewhere.

CachyOS uses this one percent of performance gains? Since it uses every performance gain, unsurprising. But now I wonder how my laptop from 2012 did run CachyOS, they seem to switch based on hardware, not during image download and boot.

correct, it just sets the repository in the pacman.conf to either cachyos, -v3, or -v4 during install time based on hardware probe