I'd recommend CachyOS over SteamOS on non-valve hardware. As much as I love SteamOS on my Deck, it's highly tailored to the hardware, and has some limitations. But that comes with caveats I'll cover later.

I also find Bazzite to be too locked in, and complicates how to do things that aren't managed, for a general gaming desktop. If it's a media center PC Bazzite can be great, but can easily feel locked in if you want to start adding TV apps or Kodi.

That said, for a beginner friendly Linux distro I'd point most users towards Mint or Pop!_OS depending on their use case. If the user has a high technical knowledge and capability, but lacks Linux experience, I'd point them towards CachyOS, their docs, and the Arch Wiki. Maybe Garuda if they want to additional bundling and update management tooling.