Have you thought / researched about the correlation between a normal drive for masturbation but a comparatively low desire to actually have sex?

Thought, but not researched! I thought it in relation to the topic I was arguing, rather than the thing itself: in other words, I thought about what is more correlated with actual sex drive: masturbation, or actual sex? Can one person be a frequent masturbator but an infrequent sex partner, not because he/she can't but because they don't want to?

Feminists, for instance, could have a strong sex drive that exhibited itself with masturbation, but they might not want to have sex with the actual men they see around them cos of how feministically backward they are. And it doesn't have to be about a movement, it could be very individual, like a specific person just preferring sex with his own self cos the real thing always disappoints.

When friends complain to me they haven't seen their partners for a couple of days or maybe even weeks and couldn't have sex, I was usually like "Yeah, whatever, it's no big deal."

Agreed! That might have something to do with introversion. My partner is always alive in my head, so I don't actually need constant contact with them. I always found it strange when people would break up 'because of distance', as in they would study in different countries, and meet once every three months for 3 weeks. To me, that seemed enough to sustain an otherwise healthy relationship. Only reason to break up would be if you actually just needed the sex, not the rest of the person.

The Japanese now are going through this cultural thing where sex apparently doesn't matter much to them.

But not caring about having sex for a year is a different thing, I think, although it again might depend on what's inside your brain. I find for example that when we're younger we tend to think in terms of 'hope', and can postpone gratification, as in 'I have time; I'll do that later'. But also it might depend on hormones.

So that's a topic I will mention but not really go into deeply in the next post, because what you're asking is more about sexology and less about sex differences. In general though women do seem to be able to turn their sex drive on and off almost at will, and can go for long periods of time without sex without it bothering them (but I'm including masturbation here), and men in general don't seem to be able to do that.