As previously stated, “being a mutant” isn’t something hereditary or cultural in any meaningful sense. People aren’t raised mutant, and while they’re born mutants (except when they’re not), what does that really mean? This is again where LGBT identity is a much better guide than race or creed or culture, but even then: beyond affinity culture overt or covert, the biggest thing that brings LGBT people together is the basic human need for love. If you were a gay woman who found out that the population of gay women was reduced drastically, and that no more women will ever be gay, then your chances of romantic love have just been damaged horrifically. Not so for mutants! Mutants can and have formed romantic bonds, marriages, even had children with just about anyone. Not only have mutants loved mutants, they’ve loved baseline humans, differently-powered humans, Inhumans, Eternals, Externals, demigods, alien races, hybrid alien/humans, clones of past lovers, synthetic lifeforms, abstract cosmic entities, time travelers, ghosts, possibly themselves from an alternate dimension, I forget. If there were never more than 198 surviving mutants, those 198 would still do fine on Tinder.