I am not denying that communism contributed to keeping the nations of Eastern Europe underdeveloped. But couldn't one also say that the countries of Western Europe had a 'head start' compared to those in the now ex-communist countries, considering that they were so much more industrialised and developed even prior to WW2 compared to the agricultural, peasant economies to their east?
Even if one takes Germany as an example, one could say that most of the industry in Germany was always located in the South and in the Rhineland, whereas the East was always poor, infertile and sparsely populated (Saxony aside).
I don't want to come off as condescending, but this does sound a little bit like a straw man argument. You already seem to to know the answer yourself.
Yes, Western Europe got a head start and was already ahead socio-economically before the Iron Curtain. But I never met anyone who denied this seriously. Socialism and planned economics are not solely to blame for the underdevelopment of some Eastern European states, yes, but it's not a simple story. Plus, you're lumping together numerous nations which are and already were quite different (like for example Poland, East Germany, and Romania) and are right now performing very different from each other in economic terms.