This probably wouldn't happen for property that's low value and bulky, like furniture. But for property like yachts, planes, artwork, jewellery, etc., it seems easy to move it to a country without inheritance taxes since the relocation costs would only be a small percentage of the total value.
Am I missing something here?
(I know the U.S. has a special law to tax overseas citizen, which almost no other country has. But the inheritance tax system predates that, and international travel was still straightforward back then for those with means.)
EDIT: Originally mentioned luxury cars but then realized it isn’t a good example as cars need to be legally imported back into the country, and thus pay import taxes, to be useful. This doesn’t apply to planes or yachts though in countries that allow foreign flagged yachts or foreign registered planes to operate. Personal items such as jewellery would probably also not have any import taxes imposed when the heir brings them back.