The stronger version: how is it the case that Egypt, or Egyptians, today "own" something that has been in the British museum far longer than any of them have been alive? Even if the artifacts were wrongfully taken in the first instance, does that automatically mean that the only right thing to do is to return them, even after centuries? Are the myriad other interests that have accumulated in the interim simply not matter? How long domes something have to remain in Britain for it to meaningfully become part of British heritage as well as Egyptian? Should we also be working to return artifacts looted by the ancient Egyptians to their own ancestral homes, even though the looting occurred thousands of years ago when they were the dominant power? Perhaps they should give back everything south of the First Cataract to the Nubians. (Hopefully it's clear that this is a reductio not a policy proposal!)

That's not to say I think it's categorically acceptable for powerful nations to take historical artifacts. But I don't think this has really anything to do with "stealing" in the usual sense. if anything, that rhetoric just obscures the issues here that might truly be worth thinking about.