It's very hard to get people out of their cars and on to public transportation.

Newcastle/Gateshead for example is lucky enough to have the second-largest of four metro systems in the UK, (granted its having a few issues while we await new stock), & we also have a fairly good (but obviously not perfect) bus network.
Many of our bus routes are served by modern comfortable route-branded buses which are fully accessible for wheelchairs & buggies, accept contactless/in-app payments, are often fitted with audio-visual next stop announcements, high backed leather seats, free WiFi and power outlets and some even with tables.
However this is still not enough to entice most car users out of their cars because of course cars are still more convenient.
Therefore in central areas buses must be given priority over private vehicles otherwise car usage just continues to increase along with congestion and pollution.

Central Government have instructed several local authorities across the country (including Newcastle, Gateshead & North Tyneside) to address pollution and bring air quality levels up to legal levels in the quickest time possible, which is why some parts of the country are having to consider congestion/clean air charging zones among other measures.

Our bus network has plenty of room for improvement but I imagine the quickest way to get people out of their cars and onto public transport is to make car usage in central areas either more expensive or less convenient than public transport.

From what I've read about Central Newcastle I think the authority's idea is to get car users to think about how they approach their chosen car park so that you drive TO the city centre, and not THROUGH it/around it as this is what causes the most congestion & pollution in the urban core. (Obviously better still, try to not bring the car into the city centre, or at least not as often). In conjunction with that multiple bus priorities have been put in place around the bus loop, including improved bus lanes, new smart traffic signals, enforcement cameras, better/safer cycling infrastructure and bigger safer pedestrian areas and crossings, all so that buses, pedestrians & cyclists (i.e sustainable/public transport) takes priority over private vehicles.

I imagine the travel mode hierarchy in most growing/successful towns and cities these days will be something like:
Pedestrians
Cyclists
Buses
Hackney Carriages/Private Hire Taxis
Services (goods)
and lastly, Privately owned vehicles.

Like it or not the bus companies do have a point rallying for congestion charge zones, whether they're seen as being selfish or not.

(Although I use buses to & from work in the city centre, I am also a car user who enjoys driving - just incase you think I'm being completely bias to buses).