Iโm not going to risk passing out or suffocating from wearing one or TWO () pieces of fabric for 2+ hours that provide just about zero protection for/from me or anyone else.
Masks make the people around you substantially less likely to get infected--25-50% or so, depending on how close you are, whether/how the air is moving, etc. Lots of good studies have shown this with Covid 19 as with other coronaviruses and flus. Not just about 0.
Circulating the air is good and can make an inside space safer, but it's also possible for a steady stream of air to carry the virus further. I would not want to spend 2+ hours in a coach of unmasked people at 50% capacity.
It took me a while to wear masks comfortably. Sometimes the cloth would move in against my mouth when I took a deep breath while lecturing, so I was trying to get all my air through a piece of cloth the size of my mouth. I found that I could fit a zip tie into the two hems of my cloth mask, where it became a curved horizontal rib that held the middle of the mask out from my face and let me breath through the whole area of the cloth without trouble.
I am really worried that people will be unwilling to ride trains in a year or five years. Also that people will want huge suburban yards and basically dedensify so much that even more people have to drive than now.
All this is moot for me for a while, anyway, because I don't have a need to travel; I'd love to go see a bunch of people and places, but I know that going places increases my chances of getting infected and infecting other people, and every new infection increases the chance of a new mutation in the virus, and so I wont go anyplace very far away; two or three hours by car to go backpacking (an almost 0 risk activity because no one else is around).