This idea was one of many put forward to the government in a report it commissioned to help it reach a decision on policy for the care of the elderly. It was never a government policy.
Recently the government announced that to spare people selling their houses to pay for care, people would only be expected to pay the first £75,000 of care costs. After that the government would pay. However this is a snare and delusion and will be of little use to most people. If you are in a care home this limit does not cover the 'hotel' functions of your care costs, board, food, etc etc and the care cost will be calculated not on what the home is charging for the care but what your local Social Services would pay for the care they assess you need if your fees were being paid by the Local Authority.
To give an example. If you are paying £650 a week for a care home and Social Services assessed that you had care needs to the tune of £200 a week, only the £200 would count towards the £75,000. At £200 a week you would need to be in care for 350 weeks before you reached the magic £75,000.
Meanwhile you would have to pay the £650 a week for your care for 350 weeks, that is £227,500 and assuming you are in care for 7 years, and very few elderly people are, at the end of that period all you would get from the government is the £200 a week care costs leaving you with £450 a week bill still to meet