The infrastructure suffered more from neglect before the war and vandalism and sabotage after the war, than from bombing. And of course Baghdad had the best of it before, but now have to share the wealth so to speak. Naturally the Sunni/Baathist areas are not doing as well as they did when they were the privileged elite. The rest of the nation, by contrast, is doing much better.
I quite agree that the infrastructure was nothing to write home about long before the war! And all those thousands of bombs didn't do anything to improve it!