Other studies have proven that men can understand an implied no. They know full well what they are doing, of course they are not going to admit they are rapists. So, I think its both- a lot of rapists who know, and a lot of rapists who think the act of rape is ok, but still understanding that rape is a crime, and perform mental gymnastics saying it wasn't violent or she didn't say no and therefore they think its not technically rape (although it still is of course). You can find these comments in the original thread "it wasn't violent" "she didn't say no" even though the story is so clearly rape.

Women are socialized to soften their no's from direct to indirect. Studies suggest that men can read indirect no's just fine when they want to do so.[1] "Long story short: in conversation, “no” is disfavored, and people try to say no in ways that soften the rejection, often avoiding the word at all. People issue rejections in softened language, and people hear rejections in softened language, and the notion that anything but a clear “no” can’t be understood is just nonsense. First, the notion that rape results from miscommunication is just wrong. Rape results from a refusal to heed, rather than an inability to understand, a rejection."

By the way his original post was edited. It said

"She said she wanted to leave, but I reminded her she promised sex and couldn't leave (she was at my place without transportation to get away)."

He knew he raped her, but for some odd reason he decided to defend himself to reddit instead of just asking for legal advice. Even though you can still tell he raped her in his version. So, still might be a troll.