Just as I understand there is some Cuban goodwill with respect to the doctors they send abroad - and early on Fidel's creation of better literacy/healthcare programs.

But remember this: Fidel worked with the Russians to put nuclear weapons 40 miles away from the USA - and created a crazy situation - the closest the world has ever been to full blown nuclear war. That was this man's hubris - he nearly helped put the world on fire. That kind of existential threat is not easily forgotten. Point being: the 'embargo' is 100% Fidel's fault, and he could have easily taken steps to have it removed, but his ego would not allow it.