I honestly don't think it's that complicated, no. I think it's literally a drop in the efficacy of sex appeal - people seem to get the whole intimacy aspect of it just fine, and if anything Gen Z's a lot more emotioanlly intelligent regarding that sort of thing thanks to dramatically changing sexual mores where, like, consent and shit is actually valued. Most media does not use sex scenes to particularly good effect, especially video games where the limitations of 3D game engine animation have lead to very wooden scenes and often more egregiously just bad writing.

Like you're kidding yourself if you think the sex scenes in your typical Hollywood movie have any particularly deep meaning to them. Of course they've been used to draw ipeople in. "Sex sells" has been a motto for decades. There's certainly movies that do use sex scenes well, that aren't awkward payoffs to arbitrary romantic subplots, but I don't think the generalized lowering of interest in those scnees specifically comes down to gen z feeling less intimacy or whatever moralizing flaw. I think they just have higher standards lol.