I can fall asleep almost anywhere. I routinely fall asleep in the break room at work. Once, I was helping a friend fix his car, and I fell asleep on his garage floor when he went inside to get water.
But in a hot metal tube tearing through the sky, with my neck all kinked? Get out of here, man.
I’m 5’8" and that doesn’t work for me, there’s not enough room between me and the seat in front of me to fold all the way over onto the table before my head hits the seat in front of me.