Governments have had a year to redesign buildings , redesigm schools and hospitals

I once had a summer job standing up on a mobile scaffold with a glue brush and a roll of tape sealing leaks in the airconditioning ducts of a large glass cube modern hospital (50 years ago, but the design is not very different now). If one minor quality control glitch could give me a job for two months imagine what completely replacing the airflow systems of every glass cube building on earth would take.

It can't be done. But mask wearing is doable