Dongbei drivers are famous for their interesting driving (but I’m going by hearsay and that one famous song about it).
I don’t think horns were used much in Beijing even on my first trip in 1999, although I do remember the Japanese guy driving us from the airport in a Jeep using it (and also seeing lots of city buses out at night without headlights on, you don’t see that anymore).
I just got back from Beijing a couple of weeks ago and honestly…the traffic is still very horrible but fairly orderly. Just too many cars and not enough roads (but it’s always been like that).