Going back to the OPs question - would it be a deal breaker to date someone who’d never been in a relationship? I think most have said, not necessarily but would need a bit more info.
The more info is that he loved a woman for 13 years, she was perfect but turned him down because he didn’t know how to do sex. OK. That’s a bit odd, not sure we’re getting the full picture here. Start scanning the horizon for flags.
But he paid a sex worker to workshop that, the sex thing is sorted, the issue is I can’t get a girlfriend because I’ve never had a girlfriend. Many came along saying, yeah, the paying for sex could well be a deal breaker tho. At the very least we’re getting into ‘ick’ territory with that. So he said, well, I’ll just lie about that. Then it became ‘I lied about the sex work thing anyway’. Red flags began to flutter.
We also got the ‘I’m a nice guy. My boss shags women in exchange for work/promotions’. OK. A different sort of sex work I suppose, but the red flags move to flapping.
People try to tell him that he seems to have a problematic view of what a ‘relationship’ is, give him advice about communication etc or suggest that a therapist might be a better approach. We are left with nothing except the sound of the red flags flapping in the breeze on that.