Few of those are ever running. Mostly we have just two brands of smooth-brains whose only policy aim is “preventing that other group of assholes from gaining any power, because they and their supporters are pure evil!”
Each side gets the smooth brains they crave because for ~50% of the population it's become a team sport / religion situation. A majority of people have not thought through 1/10th of the policy positions they automatically support/reject based on the team hat color.
There's a quote I will mangle and I forget the source of that's something like "If you agree with all the positions of your chosen political party, either you have thought through every option and came to the same conclusions on dozens of topics, or you haven't thought through anything".
> because for ~50% of the population it's become a team sport / religion situation
It's kinda even worse. We can only have two parties because of FPTP, and turnout is about 60% of voting-eligible population on average. We know from recent popular vote that that 60% is split roughly 50-50.
So 30% of the voting population is Team Blue Hat, and 30% is Team Red Hat.
If you can get 15.1% of the population to vote for an unserious clown, they'll win their respective party's nomination. And in most states, one of the parties is a pretty sure lock in the general.
15% is a pretty low bar. Compare: Up to 30% of people think "chemtrails" are at least a "somewhat" real thing, and 5% of people believe vaccines contain microchips. So the bar for getting a guaranteed win is somewhere between those two wacky and easily disproven beliefs.