A lot of these changes are coming in the wrong order - first you improve public transport, create affordable housing near city centers, and drastically reduce the price (and let’s be frank, increase the quality of) public transport, and THEN you hit car users to push them on to these options. In the current order, they just introduce further hardship to folks who already have a bad time.
It might be a little different in the UK, but in North America step #1 needs to be “first you abolish the low-density zoning restrictions that displace almost everybody far away from the city center to begin with.” It’s not just that walkable housing isn’t affordable; it’s that it’s not even allowed by law to exist.