Agreed. It was literally the wake up call for the fact that air quality standards are as important as soap and handwashinhg are, and yet... nothing happened.

And so the question of what effects getting rid of several-yearly respiratory infections would have on our health and the development of children remains open.

I don't know how general it is, but my dentist and kid's school kept the HEPA filters after covid. It's at least... a little better?

(Speaking personally, my home indoor air quality is now awesome and I love it. Wish it hadn't taken a pandemic to clue me in, though.)