Both major parties are to blame. The Tories introduced right to buy, but Labour, who endlessly denounced it as pure Thatcherite evil, had many years to reverse the policy, but didn't. Why not? Because they thought - almost certainly correctly - that it would lose them votes. I know at least one diehard Labour voter who was only too happy to buy her home at a discount.
Tony Blair loved a load of super-rich people buying in London - he pontificated about the 'trickle-down' effect, which is a sick joke. Exactly the reverse has happened.
The one thing the current govt. has done, and not before time, is to cut down (and eventually abolish) the tax breaks for landlords, which skewed the market so unfairly against owner occupiers. In the short term this may have the effect of raising rents, but in the longer term, the number of landlords selling up because it's no longer easy money, or they can no longer make the sums add up, should help to bring prices down.
In an area I watch closely, in SW17, the price of 2 bed flats has already come down quite a bit - albeit from a completely crazy peak. E.g. a relatively spacious 2 bed Edwardian maisonettes with its own garden - originally priced at just under £600k - yes, it's mad, but not unusual a year or so ago - and this was in Tooting! - actually sold for £525k.
IMO there should be a lot more control and restrictions on social housing - there is supposed to be a lot of fraud, including people using all sorts of dodges to 'qualify' for right to buy, for properties which they later just rent out. Also, on a TV documentary some time ago, a man was shown to be trying to sublet a council flat in a prime area of London - for a lot more rent than he was paying the council - when he owned another flat just across the landing! I doubt that he was a one off, either.
I suspect that there is quite a bit of looking the other way, not to mention brown envelopes, within council housing depts, too. There has certainly been some of this proven in the past, and I doubt that very much has changed.