If you look at many historic city centres in the Netherlands the solution is to changeover a fraction of those narrow streets into single way streets + cycle path. There is now enough evidence that more lanes does not improve traffic it is just met with more cars to match the increased capacity.

In my city it would be trivial in most roads, you would just have to remove parking on one side. Unfortunately the needs of 10 car owners living in the street are more important than the needs of everyone else...

Of course they are, because the people live there.

The people biking and walking and riding scooters also live there. I'm not sure why 2 out of 3 lanes should be dedicated to people parking their cars.

If you want to live downtown and own a car, you can rent a parking space in a garage.

Then ban or severely limit cars there. You can turn a 2-way street into one way one and turn the other lane into bike/e-mobility one. If not that make it 30km/h zone, allow bikes and allow other mobility devices to take the middle of the lane. Banning cars from some streets is great solution as well.

Wonderfully put, but I take objection to saying "severly limit cars" what you are actually doing is increasing the throughput so that cars can actually get anywhere. Leaving it at status quo limits cars severly by making congestion worse.

You'd be surprised!

Cars are an incredibly inefficient way of transportation. You can easily fit 10x as many bikes in the same space as a car lane. By building a viable biking / scooter infrastructure you reduce the amount of cars on the road, which more than makes up for the space required by this infrastructure.

Besides, car-heavy tend to be designed quite badly. Planners have a tendency to design for the worst-case scenario, so you end up with communities which legally require a 40-foot wide street in a quiet residential area. You simply don't need that much space!

Just a question of priorities

That depends on how many lanes they devote to cars. Most of the main roads near me have at least 2 lanes in each direction - sometimes the inner one is devoted to parking, sometimes to cars, sometimes just to busses and bikes.

Ahahahaha. In a twisted way, you are right. Such is the entitlement and the decades of car dependency that daring to remove even a single lane (driving lane or parking) from the almighty Car traffic, be it for a bus lane or a tramway or a bike lane, sparks incredibly virulent backlash.