Do you think it would ever be desirable to eliminate all noise in cities?

Actually, I don't think eliminating all city noise would be desirable - it would feel unnatural. Some background noise gives cities their energy and character. For example, in Shanghai where I live, hearing street vendors calling out or the distant hum of traffic actually makes me feel connected to urban life. That said, excessive noise pollution is definitely a problem - like when construction work near my office makes it impossible to concentrate. The balance is having quiet spaces like parks for escape, while keeping the city's natural soundscape intact. Complete silence would be just as stressful as constant noise.