I read something in passing a while ago and didn’t care to investigate the claim so I’m sorry this is just heresay, but the claim was the amout of variety in the modern genetics of humans makes gene defects from incest less likely than it has been in the history of the species. Obviously this one’s gonna be case by case but I’d assume if it holds true it’s for more diverse populations probably from nations with lot’s of immigration and probably still really risky if you share parents. But again, I really didn’t feel like spending time investing that.