I too was in Potsdam in the mid 80s and the taupy-gray of all the buildings, ruins from the war, and totally faded glory of what wasn't in ruins was a sight to behold. It seemed a combination of sadness, ugliness, and withered beauty that was, in a strange way, romatically attractive. Europe before McDonald's for sure.
Arturo, going back to the original post, did Wilhelm II build or rebuild these palaces as suggested in the TV show? I thought not. I know he "remodeled" the grand entry hall in the Neues Palais with semi precious raw stone work.