Do CachyOS optimizations actually make any difference whatsoever? I know they enable certain optimization flags whenever building software, but that doesn't directly equate to performance improvements unless you're actually benchmarking and testing it. I've seen some benchmarks in games and it seems there is literally zero performance difference (sometimes it loses to Fedora, even).

I'd always recommend upstream distributions with corporate backing for novice users: Ubuntu or Fedora. If they're coming from Windows: Linux Mint. There's also a clear upgrade path for users who enjoy Mint or Ubuntu: Debian testing.

Arch Linux is awesome, don't get me wrong. I just believe it's borderline unethical to recommend someone installing anything related to Arch on their workstation. It's just not what a beginner should choose at all. CachyOS included, it even makes you choose your bootloader at install (any user-friendly distro would simply never bother you with that and go with GRUB right away).

A user's first distro can make or break their Linux experience. Think hard before recommending new users the flavor of the month or an Arch derivative.