The answer is to build more houses, in order to control the supply and demand related house price rises, and to build copious amounts of social housing, as any good government should do, so that government can have an impact on rental controls through competition.
The reality is that the government is just creating a situation that forces LL to sell into a housing market that is so bouyant that the prices still maintain even with the extra properties.
Then the government make the LL the villans when in fact it is their incompetence.
Bad LL who rent unsafe properties should be banned from being LL. But we still desperately need good LL. Not this current situation.