Persepolis wasn’t in great condition when I went but it also wasn’t a shambles. There’s a gift shop, guards, and a reconstruction of part of the palace, and a lot of tourists. Also a small set of offices for archaeologists. I’m a professional historian so I was a little bummed by the lack of adequate public-facing educational markers and texts, but it certainly can’t be compared to something like the Buddhas of Bamiyan as an excuse for removing items to European museums.
Leave them there, take care of them there. Stop thinking everything from poor nations is up for grabs.