Sure, if everyone knew they had perfect teeth. But most people rely on their dentist for that kind of information. Which makes you wonder if your assertion would actually turn out to be true.

Many naturopaths make a decent living.

What an absurd straw-man argument. Nobody ever claimed fluoride solves all dental problems. Or even half of them.

Yeah so there's a vaccine that kills the bacteria that causes tooth decay, but you don't hear much about it That would definitely cause disruption in the dentist field if someone were to make it readily available