Linux culture is about freedom of choice and movement. Any project can be forked, tweaked, expanded, or outright overhauled by anybody with the know-how in order to meet specific use cases. And those use cases are often the same as other's use cases. But in most cases, they are still rooted in the project they forked from. I.E, any guide that applies to Ubuntu is likely going to apply to Pop!_OS or Mint, since they're based on Ubuntu. So there's rarely a downside to niche distros, because you can have something that's close enough to a popular distro but that caters to your unique needs and wants.

For me, for example, I use Nobara. It's rather niche and in most cases, it either works beautifully for you, or it doesn't work at all, honestly. But it's based on Fedora, so any guide for Fedora is likely to apply to Nobara. I get all the benefits of being on Fedora with tweaks and patches that make my gaming experience much more stable. And quite frankly, Nobara has made my rig run the best it ever has.