My nephew is 16. He thinks he can't date a 15 year or its pedophilia. He thinks this because it's what all the other kids his age think and he is terrified of being called a pedo.

So when a girl who was a grade younger than him asked him out he said no, even though he really liked her, because he didn't want to get socially ostracized for breaking the rules. Awhile later a girl who is 16 flirted with him and he asked her out, but that's cool because they are the same age and there is no 'power imbalance'.

There is a lot of 'age paranoia' going on in online spaces that has filtered out into the real world, such that an 18 year old dating a 16 year old (which I did when I was in HS) is considered horrible and awful, not normal and acceptable.

And some folk extend this to various other ages and perceived 'age gaps'. Like 28 year old dating a 24 year old being considered 'predatory' now. It's stupid... but people believe lots of crazy/stupid things and you aren't going to convince them otherwise because they like using age gaps as some sort of measure of moral acceptability for other people's relationships.