Everyone has an excuse, but two wrongs don't make a right. Drivers are not justified to create noise pollution because pedestrians or other drivers are indulging in inconsiderate behavior.
I've lived on both sides of the world and frankly, it all comes down to how the individual regards himself and his social obligations. S. Asia is notorious for it's poor regard of public spaces. These are foundational cultural concepts that I don't see changing any time soon.
Without a sense of personal responsibility the individual is powerless to act. The excuses you provide make the problem perpetually someone else's fault. The comment above spoke to the "entitlement of drivers" and this is the key to the whole issue.
In the west, I've seen known gangsters stop their limo to personally remove a single piece of litter from the street. These are people who explicitly live outside of the bounds of the law. This person could have made his chauffeur or assistant retrieve the trash, yet he took such pride in his neighborhood that he had to do it personally. The contrast is obvious.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3968587/ https://en.wikipedia.org/wiki/Health_effects_from_noise
My "excuses" as you've put them are situations that occur everyday on Indian roads where honking is an alternative to colliding with and running over people and animals. Noise pollution is the lesser evil.
I would never indulge in causing that kind of situation to arise. That's the limit of what I can do. If faced with that situation my greater responsibility is to avoid a collision.
It's probably hard to understand what I'm talking about if one has never experienced traffic like this themselves.
I live in India, and a lot of times it is for safety. It's not always about people crossing the road. There are people walking on the road, shoulder-to-shoulder, four deep; there are scooters driving side by side as their drivers are having a conversation; there are car and scooter drivers talking on their cellphones edging along slowly, not stopping, not driving at the normal speed of traffic; there are people getting out of parking, backing into traffic, seemingly oblivious to you as they drive backwards into you while you're stopped or braking hard; there are cattle; there are dogs. 9 times out of 10 it is for safety.
The Mumbai traffic light honking is about people honking at vehicles stopped in front of them to start driving when there's still a few seconds left on the red light. That's what the cops are trying to prevent.