Previously landlords could rent at £1000 pcm, pay their buy-to-let mortgage at £900, and get taxed on the profit of £100, at 40%, that would be £40.
Now they get taxed on £1000 = £400, and get a tiny amount of tax relief on the mortgage cost.
So many landlords were paying much, much, more tax. So quite a lot of them exited the market.
Fewer properties, same number of people chasing places, has increased rents. On top of a stupidly hot property market in London, and it's the perfect storm really.
Slow applause for the UK government on this one. They were told this would happen when they made the change several years ago.
I am seeing rental yields still under 3.5% (zones 1-2, Victorian terraces converted to 1-2 beds).