I think that the thread makes two valid points. First, the German "imperial" thinking isn't the reason for their stance, but it is the basic, background worldview from which their reasoning begins. They have viewed Eastern Europeans as being less competent for so long that it is ingrained into the German psyche much as the US views Mexico and Latin America. The economic considerations are informed and supported by this background belief. It makes German inaction more palatable to the German leaders and people.
Second, it is a very good window into how Eastern Europeans see the German mind and reasoning. The conquered see the imperial in a much different way than the imperial see themselves, usually in ways that are difficult for the imperial to reconcile with their self-image.