*trying to come off as non-offensive as I can*
I think the reason why most can't handle NTR games and feel hurt or pissed is because most players here love to self-insert themselves into the game. They pretend the MC is them, so when bad things happens, they take it way too personal. They get so invested into the story and characters, but not as a reader. So when said MC gets cheated on, they feel like those characters are cheating on them in real life, and they get all the feelings that come with it.
Thus why most prefer their "one dick to rule them all" harem games. They are self-inserting themselves as the MC, so they don't want bad things to happen cause they take it personally and feel like it is happening to them in real life (pretty sure you've seen this behavior on these forums a lot, especially in Ocean's threads lol).
Personally, I'm in the minority of those who don't self-insert. I never see the MC as myself, I just read a story for the story like when reading a book or watching a movie. I still get emotionally invested in the characters and the story, but it's from a reader's perspective not a personal one. What happens in these stories is all fiction and it doesn't affect my personal life. It's a choose your own adventure book.
Not trying to judge anyone or offend, I just notice that a lot of people on these forums tend to take these visual novels way too personal and treat it like it is their real life. I feel if people would just enjoy the story for what it is instead of attaching themselves to it personally by self-inserting, then these type of visual novels wouldn't bother them so much. But that's just my opinion on it.