If all humans weren't supposedly descended from Adam and Eves kids, maybe we would all genetically be better because otherwise we're all inbred, amirite?

Are you calling me a sandwich?

Inbreeding with close relatives is mostly only an issue genetically because it makes it much easier to pass on genetic diseases and disorders - for arguments sake if we assume that Adam and Eve were real and freshly created then we can also assume they are completely free of all genetic diseases and disorders. So their direct descendants should be okay then theoretically their descendants and genes may well have split up and diversified enough before any issues presented themselves.

Also probably shouldn't have to say this but this is in no way an endorsement of incest.

Muslims got it right

We're all inbred anyway. If you think about it, you have 2 parents, 4 grandparents, 8 great-grandparents and so on. You don't have to go back many generations for that number to get bigger than the world population at that time. This means some of those people are in fact the same people, that are your ancestors in more ways than one