There are massive amounts of Cuba supporters outside of the Western world. From our point of view Cuba sucks, but for a lot of people the basic guarantees that Cuba gives and the lifestyle is actually not so bad at all. Their government also isn't much more corrupt than in the rest of the world.

I'm sure that, unsurprisingly, if you live in a majority white country, most Cuban supporters would be white and left-leaning. If you were a Cuban that supported the Cuban regime and were happy, why would you leave, taking on so much risk and expense?