I understand that wish but equally in this kind of game people usually want to be somewhat in control of the ending and they tend to react really badly to games that make them feel like they were gotcha'd and could not achieve the ending they wanted. If we only knew the things MC knows, had no other information about what was going on, and consequently people were less inclined to warn or protect Maya because Quinn seemed less threatening, you'd end up with a lot of people who wanted to wind up with Maya upset in the end that they had ruined that relationship before they knew what was what. That might be realistic, but it's not a great game experience. Think about how people felt and reacted when they found out they could not have a happy ending for every character they cared about in Acting Lessons (which, I note, is created by the same creator as this game! He's no stranger to serious bad outcomes for characters!)absolutely yes.
as long as they are flashbacks, it's not a big deal, we can always imagine someone telling MC about it.
but when they are private dialogues they distance us from MC, making it less natural to interact with his behavior
it is clear that we are not MC (NTR !!!!!!!), but we are responsible for him
It reminds me of how in other games and stories you frequently kind of know how things are gonna go. No one's ever written a huge game or a novel series about a hero who fails in the end and the bad guy wins. At worst maybe you lose some companion characters you care about or even the protagonist dies heroically, but you mostly know the good guys are gonna win, and if it's a series you usually know the good guy's gonna survive (Game of Thrones subverted so many expectations exactly because it's so singular in Not Doing This and making people feel insecure about every character's fate, and the main way it's able to do this is by not really having a protagonist).
People want agency and want to craft the story to their liking (and probably their fetish, in an adult game), but they don't want a bad ending, or at least they don't want a bad ending that they can't easily hit the back button a few times or reload a save from 5 minutes ago and make the opposite choice.
Like, one entirely realistic outcome for Being a DIK is that the MC doesn't make his relationship work with any of the girls. That's probably the most likely one! Most college relationships end, badly.
I doubt that's going to be featured as a good ending, though!