I agree with Timelord2067, in our country, 60 years old are required to stay at home and children 18 below are also treated the same, maybe they have weaker immune system so the authorities required them to stay at home.
That could be the very reason why people on that age has been decided for stricter rules. And it's related to the protocols that's being implemented worldwide that the ones that can potentially have a weaker immune system should stay at home. But I have read people on that age complaining to the government that they should also be allowed to go out just like others.