That, plus most of those vaccines were tested for 13+ years before becoming mandatory. Polio was an outlier at 6 years. The cost benefit analysis made sense in that case given how destructive polio is for kids.

Speaking of polio vaccines, the field trials for polio involved ~1.83 million children, recorded 518 cases of paralytic polio and demonstrated a 71% reduction in paralytic polio. The mRNA covid vaccine clinical trials involved ~2000 children and recorded no severe covid. Surely polio vaccines and mRNA covid vaccines for kids are just the same thing because people dressed up in white coats were involved in both cases.

https://jamanetwork.com/journals/jama/article-abstract/30169...

The polio vaccines had problems and caused it in some people. Improvements in manufacturing removed that danger.