I think you're right that a lot of this is about inexperience, Shayne! At the same time, I've known men with quite a bit of experience who make some of these mistakes. In that case, I think emotional intelligence also plays a role: emotional intelligence is crucial in helping a person get out of their own head enough to be capable of focusing on the other party's experience.

As for talking about past experiences, you're right that some people might not like this. I might be annoyed if a partner acted like he simply wanted to brag about himself, but as someone who likes open communication, I like when communication about sex is open too, since (in my experience) partners not wanting to talk about sex tended to be a red flag. When a partner won't open up about their sexual history even when asked, I immediately assume one of two things: 1) they're apparently too ashamed of their past to discuss it, which means there's some mental/emotional healing in order, or 2) the fact that they're shy about sex talk with their own sex partner(s) means they're a bit immature. But as you pointed out, hearing / talking about past experiences is simply not important to some people, and it might even be a turn-off for them. So that's definitely good for men to keep in mind when deciding how much to share!

Whew, sorry to write so much, but thanks so much for your very thoughtful comment. :)