That was, and is the policy in my opinion. I think they were going to be more open about it until the press pushed them to lock down. Personally, I have no issue with this as a policy if we can shield the most vulnerable. Its preferable to sitting and waiting for a vaccine.
I am not (at all) keen on the Tory's or what they stand for but being fair, they have handled some things well (i.e. increase of ICU capacity) and other things horribly (acquiring sufficient PPE for NHS staff).
Care homes is the big issue and the Government are being roundly criticised, but it is clearly a very difficult practical problem to solve. My Grandmother has late stage dementia and is in a very nice care home which so far, fortunately hasn't been ravaged by the virus. They are locked down, nobody can visit and they are doing all they can but the staff have to come and go, and therein lies the risk.
The criticism of the Government doesn't seem to offer any solutions. Care homes are like prisons full of very old and very ill people and this has been a problem across the world. Extensive testing is needed but if people are asymptomatic, or don't present with symptoms for weeks while being infected, that won;t solve the problem. If the virus gets in, then it goes round like wildfire. Its almost inevitable.