I feel like this ultimately isn't the right question because from what I've seen they're not really one monolithic group with like one specific issue, character flaw, or trait.

Lots of neurodivergent people have difficulty dating and so do misogynist pigs and so do bigots and so do people with despicable political views.

I think the big problem is that these different disparate groups are coming together and being treated as one group and trying to come up with one solitary reason why they all have trouble dating. That's just led to a terrifying hybridization of all the worst aspects being spread throughout the group like a plague.