FFS, No it didn't. Social housing was passed on to the kids of the tenants, even if they had become far wealthier than their parents (frequently the case), so were quite capable of buying, but why would they when they are guaranteed a council house at peppercorn rent ?. Remember, Bob Crow and Frank Dobson both live(d) in council houses.
QED the stock of social housing has not changed.
What has changed since 2003 is the net increase in population every year equal to a city the size of Birmingham.