Explanation and article: https://boilingsteam.com/cachy-os-is-now-the-most-popular-distro-on-proton-db/
For those like me who hadn't heard of it:
Performance-First Linux, Built on Arch
CachyOS ships every package optimized for your CPU - compiled with x86-64-v3/v4 and Zen4 instructions, LTO, and PGO - on top of a custom kernel with the tuned EEVDF scheduler. The result: a noticeably faster Arch Linux experience with the same rolling-release flexibility you expect.