But you don't get hardware graphics acceleration unless you use nixgl, and if you want to integrate it into home manager that breaks XDG entries, which I never figured out.
Also, you are illustrating the point of the commenter you replied to: nowhere on the official docs does it recommend home manager for non nixos systems, at least not when i was scrolling through them. I learned about home manager, nixgl, and the like via forum posts, either by finding them via a web search, or by asking myself.
For example, I only found code to integrate home manager with nixgl on the nixos discourse.