The answer to that is easy. They are terrified of getting blamed if there is an outbreak of covid in their premises. Unfortunately this is a societal problem. If someone dies we look for someone to blame. The public largely do not think logically about risk, if they did they would panic less. I know someone who refused to touch a garden gate or enter a house (when that was lawful) but was willing to take the risk of traveling by car. Completely irrational but not unusual. Care home managers know that if covid gets in and some residents die, they can expect to be put in the stocks of public opinion and flogged on the village green. They know that the baying hounds will not be appeased by a press release saying that they weighed up the risks against the damage to dementia patients caused by isolation.The key question is why are so many care homes continuely failing to do individualised risk assessments and visiting arrangements?
Changing public attitudes is. rather a challenge.