The nationalization of private property wouldn’t have been a problem if it was just US property. Many countries make it difficult/impossible for foreigners to own land.

The problem was that they did it to their own citizens, resulting in many of them becoming the Cubans in Florida.

BTW, labeling them “ex-Cubans” is a good way to piss them off (maybe that is your intention). Many see themselves as Cubans in asylum just waiting for the regime to fall and for their family homes/businesses to be returned.