HMG is trying to force people to build in already traffic jammed towns & cities. The result is higher costs & ever more productive time lost in ever worsening traffic. Building new towns & > expand existing villages would avoid this
You are erroneously assuming that infrastructure to support new builds in villages and small towns exists. It's not just a matter of assigning a few fields for a housing estate and expecting things like the local sewers and roads to cope with the extra demand. For villages and small towns without meaningful public transport building a few hundred houses will not magically create a bus route, nor necessarily reopen the local pub or village shop. Furthermore, there also has to be enough (worthwhile) jobs locally to prevent "higher costs & ever more productive time lost in ever worsening traffic" and long commutes.