You’re spot on and that’s what this discussion helped me figure out: I have no problem. I knew that but I also thought that NixOS would bring something new to improve my Linux usage. So far I still see such improvements for servers or deployment on several machines but not for a single user with standard needs (and this statement may be wrong and due to my limited experience with NixOS).
But NixOS approach is quite different from others and I feel like I may discover something of interest to me once I learn more about it. Also, just for the sake of learning and discovering, I will continue experimenting with it for a while.