I’m still not sure what he’s trying to achieve by switching. Is he having issues with pop OS? Or does he just want to try something different?
I would say anything Ubuntu based will be so similar as to not be interesting, so maybe pick something different. Nobara and Garuda are different, but I honestly don’t know what they offer to someone looking to try something new since they essentially do all the config for you. So my recommendation is one of the following:
Fedora - most nobara guides should be compatible, but it does require a little effort to get set up (not a ton, just need to install stuff)
Tumbleweed - rolling like Arch, but without the upgrade issues; it’s what I use and I think it’s solid
Mint Debian edition - should be pretty similar to pop OS since Ubuntu/pop OS is based on Debian, but perhaps different enough to be interesting
Those are all major distros and thus should have lots of help available online.