And I'm saying that there is no acceptable minimum grade for outdoor climbing that isn't ripped, potentially uncomfortably so, from the speaker's own ass.
I agree, a 5.4 sport route is probably a waste of bolts. That doesn't mean that they should be explicitly prohibited, either officially or by the community at large. If we just say "all routes must be 5.9 (for instance) to deserve bolts", then two things will happen: a lot of otherwise good (not great, or classic, but good) routes will get put up at 5.8 or under that are straight up death routes for anyone trying to break into that grade AND you'll see pretty serious grade creep as more 5.8, 5.7, even 5.6 routes get called 5.9 just to fit this arbitrary cutoff.
If you develop routes and are concerned about crowding, then don't develop a crag that will have that problem, at all. Don't put in the bolts for harder projects, don't put in the bolts for warmups. Don't develop the crag period.
You're arguing for a universe where climbers who can't onsite at a certain level don't count. My claim is that whatever the cutoff, it will be arbitrary, needlessly elitist, and counterproductive.