You won't pay capital gains tax in the UK if it's your main residence? Income tax lol. No I want to see landlords paying 30% say of their rent into the local authority! There is not enough stock, which forces values to climb, it's all to easy for people to go overseas and retain their properties...
I totally agree with you, to many people move out of towns and cities these days for pastures new but for some reason rather than recycling their property to the local sales market which increases stock and slows value rise they let their properties out!