Non-free drivers don't get added to the kernel just for fun. They're there because hardware won't work right without them. So if you have such hardware, then running an entirely free distribution will make your system objectively worse, and if you don't, then the non-free drivers weren't getting loaded anyway, so running an entirely free distribution has no effect whatsoever.
I've been meaning to try GNU Guix for a while and haven't gotten around to it. Distro hopping is a pain in the ass when you have a lot of other stuff going on.