Really I don't think that Pureblood society is all about classicism, eugenics and elitism. 🤔 Originally it is not and I totally understand why they would want to preserve the original ancestral lines of magic.
This may be a broader subject but I think the original motive is quite beautiful. It's just that it has accumulated so much abuse and pain along the way. I enjoy diving into this world though, even if we don't hear that much about it canonically. Even more fascinating to think about these unseen parts. 😊