Having kids with your 1st cousin is rarely a problem unless it’s a pattern that’s repeated over several generations. I still think it’s kinda weird, but as you say, that’s a cultural aversion, not one that rises organically out of fear of inbreeding. That said, the incest taboo is one of a handful of human universals, like music, language and fire, to name a few others.
Having kids with your 1st cousin is rarely a problem unless it’s a pattern that’s repeated over several generations. I still think it’s kinda weird, but as you say, that’s a cultural aversion, not one that rises organically out of fear of inbreeding. That said, the incest taboo is one of a handful of human universals, like music, language and fire, to name a few others.