Could you provide some examples?
There's plenty examples on https://en.wikipedia.org/wiki/Congestion_pricing
Demand is demand to get to a destination. If public transport is effectively run and managed, it may be the better option for a lot of people.
Over a short timeframe yes demand is demand and it's not going to change much but people also move to different areas and a big consideration would be the difficulty and time of the commute. What that ends up meaning is any reducing in demand on an individual road will likely just mean people moving to take advantage of that.
You are right though, but to ask another question, would you support making those roads smaller with toll monies? I could imagine this ending up with roads only being used by the rich type thing.
What's the appeal in making it smaller? I could understand that in the concept of maybe converting some into rail or other public transit infrastructure. Generally I think commuting to work in large CBD by car already has become a "rich type" thing with the cost of parking I think focus should just be more on having good alternatives.