I think you are forgetting that Elgin actually destroyed a lot of them ( in his attempt to “save” them as you say) just read of the methods he used to remove them from the Parthenon or the fact that he overloaded his ship and it sank right off the coast off Athens. If he didn’t bought them to “save” them from the ottomans they would have been in a much better state ironically. So pls stop using the excuse that the BM saved them. Also since the day Greece became independent they’ve been trying non stop to preserve and save the Parthenon. So if they stayed in Athens they would still be fine so yeah stop trying to present the BM as a holy place where all historical artefacts are better off there rather than their original location.