Are you suggesting that the ENTIRE world shut down and destroyed economies even though we know EVERYTHING there is to know about COVID-19? Those two don't fit together.
So, what exactly are you trying to convey? At this point, it appears you are saying it seems to have an inconsequential impact on society?
Post viral immune modulated disease is not new. With your depth of understanding of the "science", one would think you'd be up on this. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6723519/ https://www.webmd.com/children/what-is-kawasaki-disease