Yes, they are already doing that. Tourism, exporting skilled workers (doctors), exporting rum and cigars. Exactly the economic activities that do not require external raw materials. And with that, they have achieved social indicators vastly better than all their neighbors. So I don't really see the basis for your accusation of incompetence: Cuba does well what it can.

But what it can do is fragile. Without industrialization, there is no way to have stable wealth. China and Vietnam themselves only industrialized and followed that path after trade blockades were lifted. Without that, the Chinese reform and its opening to the market would have come to nothing.

Moreover, it is strange to defend a crime by naturalizing the idea that the criminal will always act that way. That may well be the case. In that case, it is morally necessary to turn against him and stop him.