Not vaccinating children leaves them vulnerable at some later stage in life. Currently, most (but definitely not all) young people do not appear to suffer much

Not vaccinating children leaves them vulnerable at some later stage in life. Currently, most (but definitely not all) young people do not appear to suffer much damage from an infection. This is definitely not normal for virus infections, e.g. the Spanish flu killed mostly young people. It also means that the most successful variants in the future will be those that infect children. This is just natural selection. It will also mean that vulnerable persons will have to be very careful with interacting with children.