OP I think you are absolutely right.
Obviouslt NAMALT etc 
- does this still really need to be said? I'm not in a relationship remotely like this now but I still think it's a cultural pattern which is useful to recognise.
Enough men ARE like this for it to be a widespread problem.
It comes from multiple angles as well, and it all feeds back into itself like a cycle.
Culturally, sex = PIV, focused on the male orgasm/male arousal, as in, you NEED an erect penis, otherwise nothing is happening or it's certainly not considered "the main event", the male orgasm is also thought of as the "natural" stopping point. The female orgasm is treated as some kind of impossible side quest or if you're lucky something to be got out of the way first or attended to afterwards like an afterthought. But many men don't give a second thought to how to achieve it, they just expect it to magically happen during PIV sex.
I reckon a lot of it is conditioning as well. If the majority of your sexual experiences (early or always) tend to involve orgasm, good natured experimentation, communication, connection, fun - then you're going to build up a positive association where sex = good feelings. For men I think this is fairly likely to be the case, and also for some women of course. But for a lot of women it's not - and if the majority of your first experiences of sex are not associated with these nice feelings, or even worse are associated with feelings such as discomfort or pain, (how many people are/were told "it always hurts the first time"?) unpleasant bodily fluids with awkward clean up, boredom, obligation, physical activity with no reward then your association is going to be far less positive - and I'm not even getting into the fact that unfortunately a large minority of women have sexual assault as part of their formative sexual experiences so you can add pain, trauma, fear and violation to those associations for those women - and if you've been raised with oppressive views about sex (which I think is unlikely in this country in this decade, but you never know?) you can add guilt and fear from that angle as well. Fear of pregnancy ought to affect both sexes but tends to be more real to women, as we are the ones who would actually have to go through it - and tend to do the thinking in terms of need to take a pill/make sure he uses a condom, is my period late? Do I need a morning after pill? Plus side effects of these hormones.
So if you get past those initial experiences, then the majority of men have built up a positive association with sex whereas I think a lot of women - I want to say a majority? But I don't really know, and I have been told I'm painting a really grim picture of this on here before and apparently it's only a minority - but anyway - let's say women are more likely to have a range of associations with sex, ranging from "best thing ever" through "nice warm fuzzy feelings" to "bit of a hassle, ultimately worth it" "alright but massively overrated" "boring/uncomfortable/tiring, maybe dangerous" right up to "frightening and traumatic". In my experience, men (even nice ones who are good in bed and interested in your orgasm) just don't get this. They assume that everyone has the association that sex = nice, warm, fuzzy feelings. They know about the frightening/traumatic response but they hugely underestimate the number of women this affects and also assume that if you were traumatised by sex you'd tell them, whereas many women who have been assaulted or traumatised by sex don't recognise that this was sexual assault (because it was not a stranger in the bushes with a knife) and/or they feel ashamed and don't want to tell people about it. But men don't know about the in between associations women have with sex, and I would guess that for most women the in between ones (not the best thing ever, not scary or traumatic) are the most common.
So there is a massive disconnect between how men see sex and how women see sex but also in how men assume women see sex. So men then go to offer sex to women as though they are suggesting some kind of amazing treat - the woman if she does not have an overly positive relationship with sex receives this as though he is suggesting doing some kind of exercise class or cleaning the kitchen sink, and understandably, is less than enthusiastic in her response. Man interprets this as "She doesn't really like sex" rather than "She hasn't had very good sexual experiences". If this is then repeated with poor-to-mediocre sex for the woman whereas the man has an okay-to-great experience, it's reinforcing the exact same things but it's what they both expect so don't try to change it.
There's loads more that feeds into it as well - porn (aimed at men, largely consumed by men) tends to represent heterosexual sex as a display of domination/aggression rather than mutual exploration, communication, connection, pleasure. Spontaneous vs responsive desire feeds into it. Fluctuation of a woman's level of desire around her menstrual cycle vs the fairly consistent level a man has. YES domestic load/emotional labour - MASSIVELY.
The whole idea of "consent" is fucked up as well if you think about it. You don't "consent" to something fun, usually. You consent to things like medical procedures, sharing your data or a photograph being taken. If your best friend suggested a day at the beach it would not be a natural response to say "I consent", you'd say something more like "Great idea - I'll bring my beach ball" - consent is heavily implied by your enthusiasm.
I liked this article a lot: medium.com/@enagoski/pleasure-is-the-measure-d8c5a2dff33f