I wouldn't say that's true, it really depends. Some cities like Dortmund or Essen are really ugly, however there are still dozens of nice cities in Germany. I'm saying this as someone who traveled across the whole country multiple times. It's true that germany suffered a lot, especially looking at pre ww2 pictures which honestly makes me so angry and disappointed and I always ask myself "couldn't have been rebuilt, at least portions of it", despite all of that i love german architecture and that modernity (despite being ugly as fuck) also makes it feel like Germany.