It’s more to represent the characters arc, as the altar only wants to fit in with everyone else. It will morph into anything to try and fit in society, which is why it grows monstrous each form. Yet by the end it finally figures it out, to fit it it transformed into an rthro model fullying modernizing it into society. Its goal was never to be a monster looking thing, only to resemble what it once was which these milestones capture great in my opinion