The boy had experiences with each of the two archetypes at university.
One was one of his suitemates (they put 6 random people together in a shared suite, half male and half female). One of the guys, Nial, ended up being an Andrew Tate disciple. When they'd all go out, he'd hit on women way too aggressively and with little smoothness, and then get pissed that they wouldn't fall for his obvious charms (instead of thinking "huh...something I'm doing isn't working, maybe I should adjust my approach"). In short, the problem was everyone else, never him. Finally, he started being abusive and demeaning to two of the women in the flat. My son stepped in, that really pissed him off, and he went off on him. He moved out, they don't speak any more, but when they see him around, he still isn't ever with a date, and still seems to be an angry dude.
The other was a roommate he interviewed and then let move into his next flat. He was an intern with Barclays, doing technical work for them (the UK has a sort of hybrid higher ed-intern thing people can do, instead of university). The job was 95% remote. So, he just stayed in his room. All the fucking time. Terrible hygiene, the room smelled. He'd leave food out in the kitchen, have food rot in the fridge, never take out the trash. The boy tried to include him in some group activities, including girls. Fella was just so painfully awkward. He even admitted at one point, when my son laid down some rules on how to live like a civilized human, "yeah, I guess my dad should have taught me some of this stuff." Eventually, he flamed out and moved back home.
Those are the two closest examples, but I'm sure the boy could share a shitload more. He hangs out with a lot more 20 year old dudes than I do.