And was the contagiousness of covid perfectly understood as soon as it was discovered?

Certainly by the time vaccine mandates came around, we had a pretty good idea of the contagiousness and lethality of the disease.

At that point, they had also taken the caution tape off the playground by me. I'm unaware who mandated that. As far as I can tell, many aspects of the disease and vaccines are still quite controversial, though it seems to me that vaccines are helpful.