My guess is that the Government want to kick start the construction industry and thereby provide employment for many.
However, is relaxing the planning application going to do this? Personally I do thing planning is a bit of a problem and a rip off by the Council but it is an evil that is required relaxing it could lead to poor housing in the wrong place and no proper infrastructure to support it - think schools, hospitals Police/Fire etc.
IMHO we should be looking at redevelopment of Brown field sites so maybe relax some of those applications, bearing in mind what I mentioned above. The big problem here is the astronomical tax put on skips, it is a crazy amount and needs to be reduced to zero.
Then there is the other problem. I know from personal experience there are still problems with getting materials. Plaster is still like rocking horse poo and many other items are in short supply so until that is all sorted there is no point in amending the planning.
All in all I dont think the Government really know what goes on outside of the big business that their sponsors are.
https://uk.reuters.com/article/uk-britain-housing/britain-targets-red-tape-in-bid-to-get-more-homes-built-idUKKCN25133I