I definitely felt this when walking through the city center of Florence last fall. The streets and piazzas were jammed with thousands of tourists but it felt remarkably quiet, due to the almost complete absence of cars.
The noise of actual people on the street is also quite pleasant. Talking, laughing, footsteps, etc. it positively adds to the atmosphere rather then detract from it.
I guess that depends on opinions, there is a committee of citizens in Florence named "Ma noi quando si dorme?" (that can be roughly translated to "But when are we going to sleep?" ) by residents that protest against the noise by customers of bars and similar that talk, laugh, sing, scream, etc. in some streets of the center until well after 2 AM.
It is news of these days that, beginning in May there will be 24 "stewards" on fridays and saturday nights to help "educating" the customers.