Finally, someone else who is aware of the CO2 rebreathing issue with these masks! And the cabin altitude most airliners are pressurized to will just magnify those adverse effects. Even more so with smokers.
Looks like there is a US senator who is introducing legislation to make masks mandatory on airliners since the FAA administrator refuses to do so.
I see this evening that our illustrious governor has just made masks mandatory, basically, for all California citizens when outside their personal residence. It will be interesting to see how that flies, given that several major law enforcement honchos have stated they would not actually enforce the directive. I had made the comment a couple of weeks ago that the easing of restrictions came about not because the initial objective was accomplished but because it was becoming obvious to the political leadership they were about to lose control of their flock.