This is what a developer answered me on steam:
[We have made no secret of the fact that HD images as we have planned them are done. These are not easy to make, as they cannot be made easier because each frame has to be drawn by hand, and take a team of 2-3 animators 2 months to produce the full sex+climax loops for both male and female protagonists for every character we do this for. That means, for example, if we made HD scenes for every farm monster x farm monster scene, it would result in adding something like 30 years of labor to the project with no other animations at all getting done. If we add more party members, which is not entirely impossible, then they will get HD scenes as well, but there are other animations that need doing as well.]
I think it's as if you hired a single guy to build a building... obviously it would take 100 years to finish it. However, there are companies that build the same buildings in how long? 1 or 2 years...
I think the problem here is that they do not want to distribute the cake. Because if they hired people, they could be able to make a decent game and not excuse themselves in that stupidity of spending 30 years to make shitty animations. and they do not even have the descent to add a static cg at least for the "dates". I don't understand how people keep paying for this.