The ratings are pretty accurate. Game isn't good. It's a terrible slog-fest, combined with shitty dialogue and rather boring MC. People need to stop chalking it up to early NTR. It doesn't exist, and people understand that now.
Point is the sex scenes are godawful, you can find better ones just looking at JAVs, Porn, or even other games here, and they at least have story relevance. Here they're an after-thought and not really worth the effort to see them. Since they're not even interactable, they're just shitty 3D porn, that you could see by looking at anyone from the animations tab, at least there you got a lot of variety.
Ultimately Subverse does porn terribly, game isn't that fun, story isn't good, and the overall cast is just eh... I could find better casts of characters in other stuff found here. But the most damning factor is as a porn game the porn just sucks. I could look up the scenes online, and they're not too different from just watching another creators animations.