Come on bro, I can understand and agree with your other points to some extent, but this is just not fair.
First of all, the guy is clearly attractive. His jawline is so sharp it could cut glass. He has an athletic body, don't be fooled by the spaghetti arms at the beginning, we all know it takes you only two sessions at the gym in Wollust to tone up your muscles and abs. He has that dark, "mysterious" aura that young girls are so prone to fall for. And having an attractive appearance, he does not even try to get the attention of girls or somehow please them. What young 18-year-old girl wouldn't be at least curious about such a "unique" dude.
Secondly, when the MC makes his first acquaintances with girls, pay attention, no one falls in love with him yet. Bella is forced to hang out with him because of a common project. Mila is simply a friendly person, plus she notices some hidden issues he struggles with and this builds up her interest. Only Vic simply liked him at first sight, and the accident they experienced together created a certain connection between them.
Thirdly, other girls have a "secondary" interest in him. Some of them are curious about this guy who hangs out with Bella all the time. Someone caught him in the bathroom with Robin or heard rumors about it. Someone knows about the fight with Sai. In short, everyone’s interest in MC does not arise out of nowhere just because he is the MC.
And finally, isn't it a common feature of all AVNs that most of the girls we see are LIs, side girls, or at least friends of the MC. Not many people can, like Ocean, populate a game with several dozen female characters and try to give each of them some attention, at least showing them in the background a few times. Of course, most of the girls will be potential LIs or lewdable and will be interested in the MC, since those who do not fall into these categories are not even visible to us