Honestly that seems like a cope, Most Vanilla fans don't even touch ntr games . The people who even consider playing this sort of games fall into various category from corruption to Full on hardcore NTR. I don't need you you explain about the genre. But from what i have seen from the internet it has to do with the intensity. Corruption fans and some ntr fans want light stuff where the girl eventually returns or a true end while some others want full on heavy ntr stuff like yourself. If anyone is fighting among themselves its the cucks.
As for me i am only here cause i played demon harem and Fox girls. I liked the lovey dovey corruption aspect of demon harem which is rare and I liked the story of fox girls where NTR(Preventable) seemed unrealistic and not in character of the girls, It didn't hurt much as the harem ends seemed more canon if dialogues /Story are anything to go by.
Agreed on the cope. Honestly, I get the financial aspect, but you can easily make a NTR/corruption game and vanilla game together (in the same game). You just need 2 base paths, one that is vanilla and one that is NTR. Alternatively or in addition you can maybe have a path where MC is unable to save FMC and she is corrupted but MC finds another love. The thing(s) I feel many NTR games do that they would not have to is:
1. Not have a "happy end" / "non-NTR"-path. I think there are way to do it and to put the agency in the players hand if they want to have a NTR or non-NTR experience and have scenes for both. After all, at least in SOME of those scenes you just would have to change the text and some minor CG details to show the MC is having sexy times with FMC and not an antagonist
2. Have all the side character chicks also get fucked/corrupted by the antagonist(s) or other people. Literally the easiest thing to do is to reserve a nice/cool/sweet/badass female character for the MC and have them involved in the plot (like in this game with Elena or Olivia) but NOT have them be taken by someone else but offer the possibility to let MC come together with them.
imo that would be interesting and something not many games do. Most games I see are either full-on NTR with 1 or 2 vanilla elements early in the story, or full on vanilla with 1 or 2 (often optional) NTR scenes.