Anything and everything would go if it didn't, or doesn't, conform to the planners' schemes. There is a wonderful art deco building in Plymouth, one of the very few buildings in the city centre to survive the 1941 blitz there, but it will be going soon to be replaced by architecturally low grade mediocrity.
I remember in 1982 catching the train from home in Plymouth to go to an interview in Durham, about as long a journey as you can do within England. From Burton onwards was red-brick industry, mines, slag heaps, terraced housing, smoke stained and war damaged. All now going or long gone, to be replaced by light industrial or warehousing. I don't do nostalgia particularly, many of these places were in dire need of replacement, but it was more than simply buildings that went.
A lovely photo essay, I've seen some before, but thanks very much for the link!