Explanation and article: https://boilingsteam.com/cachy-os-is-now-the-most-popular-distro-on-proton-db/
I think the only reason to switch would be the optimizations, right? For new users, the installer is probably nice.
You can get all the optimizations they made in Arch, too. It's very easy to get their custom kernel, just install linux-cachyos from AUR.
For other system settings, see: https://github.com/CachyOS/CachyOS-Settings