Privileging "women secretly want jerks" as a hypothesis seems rather absurd given the evidence presented.

"Yvain says he has nice but dateless friends" is incredibly easy to explain without assuming "women only date jerks". For one, it's entirely possible that Yvain isn't a very good judge of character here, or is falling victim to the "Halo effect" (they are, after all, his friends).

Amongst other things, I get the impression that he's male, and I'd wager none of these nice friends has attempted to start a relationship with him, so he presumably doesn't have a ton of direct experience with their methods, with the experiences of a female dealing with relationships, etc..

(Obvious disclaimer: I don't know Yvain, or his friends. It's entirely possible they're genuinely nice! :))