That sounds like a myth. I had a friend who lost his hair in his early 20es. People told him it's because he was wearing hats most of the time. Another friend lost his hair at the same time and was never wearing a hat. I still have most of my hair at 40 and i wear a lot of hats and always have.

Like a rubber hat? I also doubt that the hair itself "needs oxygen" so much that a tissu will prevent the dead thing to like look ok?

I'd say genes and too much cleaning away fats and stuff from the scalp.