This is very much my experience too. The difference between stout, newer buildings and old tenements are night and day. I used to live in a place made of massive thick concrete slabs with airgaps, and the only time you could hear neighbours was when somebody was using a drill, or on occasion, one neighbour singing in the shower so it travelled along the water pipes.

Other places, you can follow conversations through the wall if you're attentive and they're raising their voices.