I completely agree with you, and yet you're wrong. Wait, I just confused myself ...
I agree with the fact that motorcycle technology has outstripped the skills of many / most riders, but I think this is only manifested at the extreme low end of the rider spectrum. For a complete newbie, the extreme capabilities of new bikes are a hindrance, because it's damn frightening to have 100+ ponies lurking under your groin. Spastic new riders will have all their difficulties magnified by the power and sensitivity available.
But for someone who has learned the motorcycle basics and is becoming a good rider, it's really silly for them to self-censure themselves down to an inferior bike. Your argument is comparable to saying that only Eric Clapton should play a strat, which is silly. Better equipment removes hurdles for someone who is capable and trying to improve. If I'm trying to figure out why my lap times aren't falling (and they're already respectable), why should I subject myself to evaluating both myself as a rider and my bike (motor, suspension, etc.). Getting a bike that's "over your head" takes it fundamentally out of the equation, putting responsibility squarely on the rider to improve up to the level of the bike.