If Incest is bad because of biological defects, why is homosexual incest still bad? Why do YOU personally have a problem with it?

Let me say that I think incest is terrible no matter what, but my reasons are different than yours. I think oversexualizing in general is bad, and if even your family is sexualized, that's bad, too. But please avoid the following thing:Saying "morality is subjective" I am asking why YOUR SUBJECTIVE MORALITY say's it's wrong. Why do YOU have a problem with it.