Capitalism did not cause people to be greedy, they were already greedy. Capitalism just embraces our nature and aligns incentives while communism pretends people can be changed to not follow incentives.
Because the US has embargoed Cuba for decades to cause hunger and desperation:
> If such a policy is adopted, it should be the result of a positive decision which would call forth a line of action which, while as adroit and inconspicuous as possible, makes the greatest inroads in denying money and supplies to Cuba, to decrease monetary and real wages, to bring about hunger, desperation and overthrow of government. - https://history.state.gov/historicaldocuments/frus1958-60v06...
Citation needed on all your other claims.
https://www.eeas.europa.eu/cuba/european-union-and-cuba_en?s....
Also the embargo de jure excludes food and medicine (although de facto it is hard to export those to Cuba), but also subsidiaries of USA companies are also not allowed to trade with Cuba, so Canadian and EU companies which do business in the USA (which is almost everybody) are risking a lot by trading with Cuba, so in effect the embargo is somewhat extended by large parts of EU and Canada.
> Cuba has yet to experience a famine despite being under a severe embargo for several decades.
I honestly don’t know where you’ve heard this. I searched the news for a famine in Cuba, and nothing came up, not even unreliable sources. Where did you hear this?