I think I know why. Note that this is only my opinion. In the game, you are the main character. You are important. There are all these amazing people that you grow close too, and you matter to them. They love you, they care about you. You are important to them.
In most dating sims, even if you don’t do their route, most characters still like you. They’re still your friend, you still mean a lot to them. In dating sims, all these amazing (and attractive) people care about you. They love you, and they care about you. And when the heroine is relatable, it feels like it really is directed towards you. When you play dating sims, you feel important. You feel cared for. You feel loved.
I’ve always spent so much time thinking or daydreaming about romance and I’m finally realizing that I have all of the granted time in the world for love to find me…. so until that moment presents itself, I’ll continue working on myself, my craft and being a better person. Relationships shouldn’t be something I’m so desperate to find simply because I want to be able to have a healthy one, ya know.