You are right, but you are missing the main problem - time. If you take any game like SG, you're introduced to the characters right from the start. Ocean's spread this introduction out over six years, and we still know nothing about most of the characters. Many developers manage to finish the game in that time.Oh yeah, I don't think there will be sex scenes in the three first chapters, that, imo, will be unreal, and he is aiming for immersion. But the thing is, the whole season must have a sex scene, not with penetration, okay, I'm good with that, but at some point of the whole season Nika needs to, don't know, finger someone, lick someone, or even we could have a scene were Nika tries to have an actual fun but he can't finish for his mental state. I could be good with it too if the plot makes sense.
In games like these, they need to keep the player engaged, create an engaging plot, and establish relationships with the characters they like that can lead to sex. If I'm not mistaken, the game will have 11 characters you can have sex with. Unfortunately, that's not possible at the current pace of development. Ocean simply doesn't have enough time in his life to do this. That's why people want to see sex scenes with the characters they like before the game is abandoned.