I get your point and I never said that making relations more complex and rising amount of possible decisions would come without additional costs, it is inevitable. What I'm trying to say is I find this particular game to have a lot of unleashed potential, which due to devs decisions will stay like that. That's the way devs wanted it to look like? That's fine.
Similar path was taken in
Chasing sunsets (as far as I remember, has been a while...) for example where story is very linear and the only choices you make are about relations with two girls and still the game is great because of dialogues and story. Giving you more freedom I would put game like
Personal assistant where you are forced for some characters but relations may vary a lot, not to mention side-characters where you decide if they are even present in your story. On the other side of scale I would put games like
intertwined, already quite old
Acting lessons,
Once in a lifetime, still in development
Ripples or
Friends in need, not to mention Being a DIK ofc(but I already see you telling me about update time which is true but also it's because DPC is stubborn one-man-army). Tbh I could give some more examples but I believe I made my point here, in all these games character relations are S-tiers, you got plenty of possibilities how to interact with particular ones, it is up to you if you either like them or not and you take consequences of your actions.
Again, I think Rebirth is very good game, just story-driven with not a lot of freedom.