I haven't seen a lot of hate on it coming from regular people, but rather from those who try to cultivate an audience online. Content creators, influencers and others alike seem to see mastodon (and potentially any decentralized system?) as worse because it inherently prevents them from being guaranteed to be reachable by the whole community all the time (in case of defederation for instance), or to migrate their following along when switching instance
I imagine you think this because of medical things (heredity and all that) AFAIK It isn't used for such things, only for legal responsibility (adoption for instance would modify it), so in order to protect the position of those who actually raise the kid and the stability of their family, I don't agree with you. Not without changing the role of the birth certificate first at least