Maybe. I see your point.At my school it's understood that "hobbyists" get promoted faster. Basically backpat belts. The competitors are promoted when they are basically at the stage of beating most other competitors at their belt. I do not love this as I can see the unathletic hobbyists on some level realize they do not deserve their rank.
At the same time as a brown belt hobbyist myself I have no qualms about knowing there are lots of better grapplers than me at brown and lots when I get to black. I've had Atos purple belts roll me into a ball. I'm fine with that. I'm almost 35 with a full time job and family to take care of. I can't train every day like those kids can.
I like the idea of competitors being promoted slower if that's cool with them and their instructors. I think that makes sense.
The comp world and the hobbyist world are not even close and in many ways are continuing to have a larger gulf between them. Black belt is a highly personal thing. I would hope that most hobbyists by the time they reach black belt would be able to frame the context of their own training and life circumstances to realize that it's a big achievement, and at the same time knowing that there is a universe full of full time competitors that would wreck them.
edit - I also think the word hobbyist is thrown around too casually. I do it myself. I see it used to describe anyone that isn't a pro or heavy on the comp circuit. But if someone has gotten to at least brown belt (or maybe even a few years at purple) I think they've made the art a big enough part of their life where it's more than just a "hobby." It may be splitting hairs but I may start saying hobbyist, enthusiast, and full-time competitor.