I already wrote this earlier:Batman without the joker is nothing, always a good villain is necessary for the hero keep growing, if this game want to keep player interest needs challenges or it will be a tasteless game to achieve a victory, generally the novels have up to 3 enemies that cause problems for the hero or MC, after a while the hero wins and gets the girls, it is much more satisfying than 0 threats and being in the house all day looking at the camera and trying to slowly corrupt women.
1. It's already a struggle to overcome without Eric: you need to bend the will of 3 woman at the same time, to accept the idea of an incest harem.
2. There is no struggle with Eric, he comes in the game and starts to fuck mom. You already lost the race to mom, you start with damage control.
3. The bottleneck here is the dev render capacity. So every time the dev makes an Eric scene, he "wastes" time on a unnecessary male, while i think the majority of players want to see nice females.