Yeah... "not nice" doesn't really describe it. "Ruin" is the better word for the condition of a lot of the lots. Search for "Ruins of detroit" to get an idea of what we're talking about. (Although a lot of the image results will be focused on large buildings, there are plenty that show what the smaller lots look like.)

I think you are underestimating the difference being in range of German bombing has made to our respective countries attitude to urban resilience, and to the other commenter, our attitude to real ruins. Detroit has but a flesh wound.