Mike, here is a worrying scientific study:

https://www.news-medical.net/news/20200421/Atmospheric-CO2-levels-can-cause-cognitive-impairment.aspx

Simply put, the more people in a room, the dumber they’ll be. I was curious, and a few years ago I bought a co2 monitor that’s always on inside my home, and the only time it’s below 500 ppm is in the winter with the doors and windows open (I’m in rural France). Closed up, with two people and a dog in the house, it’s always above 1,200 ppm. With friends over it shoots up much higher. I can only imagine what government conference rooms must be like.