The majority of shows I actually enjoy either ignore that shit entirely or have the author's self-insert moment of having a character go, "Now that's fucked up" to any such things. The most recent one I saw was Spy x Family, the one character is madly in love with his sister. The child in the wildly dysfunctional family takes one look at the situation and in her hilariously understated and dry way just proclaims, "Yuck." Mind, this is after the object of his affection beats him to a bloody pulp because stop that shit.

Why have the trait? Because there are funny situations that can come from it, especially if you're willing to make the character almost entirely unlikeable. Which this show does.