It should be true, I think, that there are invaluable things displayed there in “Tibet: Treasures from the Roof of the World”. But,
They are there without approval from Tibetan people or the Dalai Lama 14th. Some are clearly against the exhibition (e.g. International Alliance against the exhibition).
Statues or Thangka of Buddha, Bodhisattvas, etc. in the exhibition are primarily not artistic objects for Tibetan people.