This is usually used in relation to the Green Belt ie “if we didn’t have the Green Belt the whole of the South East would be concreted over.” It is quite wrong - you only have to look at currently developed areas to see how little concrete is in use - unless, that is, the area in question happens to be owned by the state.  Like the term “sprawl”, it is another attempt to curtail debate.  And again the neutral term “urban expansion” should be used.  Like “sprawl” it might be a bad thing but you have to prove it.  Pure assumption will not do.

Nothing yet but you never know...