You'll find that a lot of people in threads of harem games will disagree with your first point. Netori is often welcome (MC steals girl), but netorare (MC's girl is stolen) and netorase (MC wants his girl stolen) are not, and "ntr" is most often used to describe netorare.
The post you quoted was specifically responding to the question of 'what kinds of incest' were in the game. In that instance, all the males listed are the same single person (the MC). So far, he has had sex with two neighbors (one married, one not), a fangirl who idolizes him, and his physical trainer. He has a past sexual relationship with his younger sister, having fathered her younger daughter. He's had some sexual contact (but not sex yet) with his other daughter, his niece/secret daughter, his older niece, two other fangirls who idolize him, and the non-married neighbors' daughter. Interest has been expressed by the friend of the fangirl he's had sex with, and while nothing's happened yet, it is extremely likely that something will happen with the married neighbor's daughter. There are three other women who may be incidental or may be more fleshed out in the future, and another five women have been mentioned, two of which the MC has mentioned an attraction to (an older widow and the MC's old teacher]) but who might not actually ever appear. Oh, one other woman has been mentioned: the MC's ex-wife, but the whole point of the game is that the MC has finished divorcing her, and she is presented in an extremely negative light and is wildly unlikely to be an LI.
The only person being cucked in the game so far is the neighbor's husband, who hasn't even been named in the game yet. This is, like many harem games, a very heavily MC-focused game.