This is one of those difficult situations where one person's rights conflict with another's.
If people complaining about illiberality had a grandchild in hospital (particularly a clinically vulnerable grandchild) would they be happy to have unvaccinated visitors around them?
I've posted this story before, but when my son was born he spent his first few days on a special care unit because it was a difficult birth. He was a strong baby, but others in the unit were tiny premature babies or had other problems. One of the doctors on the SCU had come from abroad, and claimed to have had TB vaccinations. This wasn't true, and it turned out that the doctor was infected. All the special care babies, including my son, were brought in for regular X rays, blood tests and prophylactic medicine. He was less than a month old.
I will never forget how helpless we felt, and how awful it was to know that if the doctor had had a vaccination we would not be going through the weeks of worry we had. As it turned out my son was ok, but that was down to luck.
I am pretty hard line about vaccinations, probably because of that incident, as I really wouldn't want any parents to have to go through it. If that means that those who have opted out of the vaccination programme can't see their children, that might be a price worth paying so that other, arguably more responsible, parents don't lose theirs altogether.