Originally Posted by ethernal

This is almost certainly psychosomatic, at least to the extent that it actually impacts breathing. The impact to airflow from wearing a compliant facemask is trivial. The change in altitude of the plane is far more significant than whatever change in airflow a person is getting from a mask (in terms of ability to release CO2 and inhale an amount of O2). The reality is that masks really aren't that comfortable to wear. So to say that "facemasks make it uncomfortable" - then that is a universal exclusion. There are hundreds of thousands of nurses, doctors, and surgeons that wear surgical masks and millions of workers that have to wear respirators - often in extremely high temperatures - that have asthma or other respiratory issues.