Before BLM, Manhattan is a weird place as to traffic and also protests. 

All of a sudden now since BLM there are different rules. But before.

Protestors have to follow strict rules.I Legal protestors with a permit are often corralled.to keep them protected and to keep traffic moving and because of things like the Boston marathon bombing, so police can watch the crowd for participants who look suspicious.

I've watched more than one anti-Trump protest up close and personal when I was in Manhattan for business. The police would make them stay on the sidewalk if they were marching from Washington Square park to Trump tower.  and police would accompany on motorcycles and make them obey certain crossing lights and not others so as not to tie up traffic. Once at Trump tower,. they would be barricaded across the street.

As to driving, traffic often inches one mile an hour and a driver can sit through many lights because there are so many pedestrians .

It is quite common before coronavirus to have angry pedestrians who hate cars and think they should be banned from Manhattan to hit a car with their hand when it is trying to make a left turn inch through a crowd crossing the street whien the light is going to turn and they have already waited through several lights.. Also to not complete the lett turn because pedestrians are in the way is a violation called "blocking the box", stuck in the road so vehicles cannot go on green. Of course, driver is supposedly supposed to wait until it's clear to turn left, which might be: never. And people honking behind because he's sitting and blocking the lane.

After you've lived in NYC for a while and you have taken yellow cabs, you realize that they very aggressively push through crowds in midtown when turning or they will never get where they are going, that and that they may end up blocking the box. Pedestrians do get angry but they mostly bend to let the cab through. Any practiced driver learned to do same and if that if they don't have the guts to do that, and to shrug when pedestrians get angry and slap the car, they shouldn't drive in Manhattan.

Now that there are lots of new bike lanes (also before coronavirus) and politicians supporting bike use, I have seen riders on bikes hit cars with their hands as they go past if a car waiting at a red light is so much as an inch over the line into a red light. Which can easily happen because one thinks one can go through but then traffic backs up in the intersection when the light is green because its solid cars for blocks ahead or someone is trying two blocks down to make a left turn through a bunch of pedestrians! So better safe than be sorry and "block the box" you wait through another red light a few inches into the bike lane and the bike riders start hitting the car because it is in the way.

Things are way worse in places like London where many streets are tiny old one lanes.

Manhattan traffic is ruthless and aggressive for pedestirans and drives both. Especially midtown and.especially Times Square! Cars do not go fast in midtown, they cannot, it's impossible, there are too many,  5 miles an hour at max.

I know for a fact that judges DO sometimes side with drivers over pedestrians when  it ends up that there's a fist fight over a left turn...

In past times I have been in Manhattan traffic, especially around Thanksgiving, traffic is basically at a standstill around the entire island, the entire island (it's only 11 miles long and usually filled with cars,) because there are so many cars and there is an event like an illegal protest or a big accident blocking several lanes somewhere.. There were more cars all the time since the advent of Uber, as borough people started using Uber to take them to Manhattan rather than the subway.

They would have NEVER allowed the BLM protests in Manhattan to happen in normal times when the streets of Manhattan had not been abandoned as they had been for months during lockdown. Half the people that lived there went out of town and nobody with cars went there. Now that it is slowly coming back to life more people are taking their cars there because it is very risky coronavirus-wise to take the subway. Buses would take hours and hours.