As I've said, I generally play for the relationship development and (though less so) stories. Its all far from the best literature to exist, but that with the combination of the visuals is very appealing to me. I don't play AVNs specifically to masturbate, though it is absolutely a factor, its more so to enjoy the characters.
Since I realized I didn't actually respond to what I think you're saying: Animations aren't that time consuming (a higher dev time / in-game display time ratio than a static render, but not insane), but making them is a skill, just like being able to make good renders is. Otter doesn't have that skill yet, and while he's been trying to develop it, isn't near a point where it can be thrown into the VN.
When he started out rendering, they were shitty quality and very slow to make, but now they're (generally) significantly higher quality and he's much faster. The same will be the case with animations. He's just starting to learn, and I don't know how far along he is, but he'll eventually get to the point where he'd be able to animate nice and speedily.
This current animator is someone Otter has worked with before, and who was much faster before. I do not know what is up with them this time around since they're very obviously not working on this VN very much. Maybe they're in the military, or maybe they're a student that needs to study, but whatever it is, they're not getting very much done for this game.
