The government, via the DLUHC, give millions in grant funding to housing associations each year. It’s not enough, and it’s way lower than it used to be, but it is something.
Houses are being built. My place is just about to sign off on a deal for a 200 house estate in Bucks, of which 25% will be social housing aka the old style council housing of yesteryear. They will be amazing properties as well. The best energy efficiency, lovely area, all for around £150 a week- which HB will pay for if you aren’t in work