So, according to Mr. Greenstein's words, Cuba was/is the only socialist state because "racism isn't a predominant feature." I don't know how he defines "predominant", but it is clear that the governing structure of Cuba is clearly non-Black and male dominated, as it was under Batista. Yes, Blacks and women have more rights now in Cuba than they did in the 1940-1950 era under Batista, but the same is true for the US, which is clearly not a socialist state. So, I still contend that Mr. Greenstein seems to have some "ideal' definition of socialism, which never has existed, similar to the ideal definition of Christianity upon the second coming of Christ.
The premise that one cannot be a socialist and a racist at the same time is flawed. In the real world socialist groups and states have been racist and misogynist, whether in the US, Soviet Union, China, Cuba, or where ever. Now, I suppose you can take the position (as this writer seems to do) that Trotskyists do today about Marxism, to wit, they say that it is unfair to complain about the repressive policies of Marxist states, such as the Soviet Union, China, North Korea, Cuba, etc., because none of them was or is a Marxist state. A Marxist state, according to this view, will only come in the future. This is sort of like the Christian theory that all will be well on earth upon the second coming of Christ. In practice, socialism is no more free from bigotry than other forms of government. Mr. Greenstein lives in fantasy land.