But genetic engineering's just a really efficient form of the kind of...selective breeding people who care about bloodlines do, isn't it?
And anyway it's not like everyone would do it. Genemods are really expensive anyway and experimental ones especially. You can't just modify everyone. I asked my daddy about that once and he said society couldn't handle it if you did. It's probably the same for magic like you said. But a few more wizards wouldn't hurt.