Here we have two examples of actually existing socialism. They have made achievement but they also have problems. However, Western Marxists have made no effort in trying to help these countries. There are no Western Marxists who have made any serious analysis of the economic problems of contemporary Cuba and North Korea, they have made no policy recommendations, they do not engage with the leaders, planners, engineers, economists etc of these nations.
The same was observed during the time of the USSR. While the USSR was struggling to deal with the practical aspects of building socialism, related to matters of economic calculation, organizational structures, production efficiencies etc, Western Marxists simply contended themselves with denouncing the Soviet Union and made no effort with starting a constructive dialogue with the scientists, engineers, economists and politicians of the USSR.
Yes by the "useless" Western leftists I mean the likes of Zizek and his followers. But people like Y. Varoufakis, Anwar Shaikh etc should definitely engage with these countries. But that's not my main question here. My question is why the relations between Western leftists and the people in AES states became one of derision or paternalism, rather than actual exchange of ideas and useful research.