Honey, I work at a scholarship office. I review academic transcripts for a living. Sure, I'm not meeting them in person, but I've seen more applications than you've met people.

Yes, the religious fundies are problematic, but there's plenty of geniuses whose poor parents had to brush up on their linear algebra and quantum theory. That's not even mentioning the surprising number that end up just taking courses at local colleges and universities and counting them for high school credit. There are homeschoolers in the US far smarter than you. They're just not a majority.