I think the two main dimensions of the problem space are “is this particular travel necessary/advantageous” and “how interchangeable are the mobility options”.

In Germany, where most cities are still car hellhole disasters we dont move away from cars, because the car dominant focus blocks both dimensions. I was amazed how in Spain you have small shops for day to day groceries everywhere as well as vibrant markets. in Germany groceries are done primarily in large supermarkets with large parking lots somewhere near larger streets. Meanwhile pedestrians are pushed to small sidewalks and cyclists somehow pushed in between sidewalks and car streets. This in turn makes it unattractive to just walk or cycle around and do your groceries in a smaller shop you’d pass by anyways going from the metro to your door. And because it is such a pain to walk/cycle or the public transport is overcrowded, unreliable and lacks the connection for the last bit, people feel in need of the car.

At core the main starting point imo. is to always redistribute the available space, so that cars are not the total dominant, but pedestrians, cyclists and public transport have enough space too. With the options of remote work, many travels to the innter city offices are unecessary and the transition phase can be aided by policy favoring remote working options.

it is true that craftsmen, delivery drivers and so on sometimes do need cars. but if that is the dominant car traffic it is much easier to fit it in, and also in their interest as they can park close to the doors much easier, when not everyone and their dog has a car parked there already.

Final thought from what i have seen in Spain compared with Germany. A walkable city is a lively city. There is more business, there is more civil servants, there is more employment in smaller shops and with that you get a thriving local economy, keeping the money circulating and the city more independant from single large businesses as main source of employment and tax income.