All excellent points! I'll be honest, I hate cuck games personally. Not because of the NTR (I couldn't care less about it when it makes sense) but because of my own personality. I have no issue with a game where your gf/wife cheats behind your back (based on your/the MC's) decisions/choices. Sure, some may still you're being cucked, but you're not (as the MC) actively paticipating in being one. I also think these kind of games (on those routes) are far better suited to FMC games for true NTR and not MC led games, where 'sharing' perhaps makes more sense.
Right, the fans of "true NTR" (in air quotes because people couple argue all day what NTR is about) generally don't want the story where the MC is really into getting cucked. They want more focus on infidelity and corruption.
That said, it's very clear that this game's basis is about swinging and netorase first and foremost. So asking for a pure NTR set up is pretty unreasonable. What the dev attempts to do on the "true_ntr" route will largely be piggy backing on the existing netorase narrative.
You could say it might be something like the typical Atelier Sakrura game. It's just that those "netorase evolves into NTR" games typically feature a male MC that isn't quite so enthusiastic about the arrangement at the start so that there is room for him to later really get into it or start regretting it and get NTRed. If he is into it 100% percent from the get go, it's a bit hard to angle for the NTR shift.
But anyways, I'm pretty chill these days. True NTR fans got a bunch of Japanese stuff. The people into netorase and wholesome sharing are the ones that are starving for good games that hit their kink. So if this game can get that main route done right, I'd say it's a success (if the dev can actually produce updates in a timely manner going forward).