They don't support really old hardware which enables to ship better optimized packages by default and other performance boosts at expense of non-gamers. I have noticed multiple times that a package I wanted was not available in classic arch repos but was in Cachy's. As far as I know it's not that different from EndeavourOS (not that I've tried it). To me it really just seems like a distro that suits ME, a bit lazy tech savvy gamer, the best and there is not any visible dirt.