And don’t forget, as you get higher the pressure decreases tapering off gradually to a virtual vacuum. If the Earth were a pressure vessel and gravity didn’t exist (as hoax proponents believe) pressure in that vessel would be constant.
When hoax believers think a vacuum is a force, I believe it is a central misunderstanding that enhances their belief.
I vaguely remember doing an experiment in physics class at school, where we used a glass tube about a 1 metre long and about 3½ cm in diameter (capacity was about 1 litre). One end was bunged, the other end was bunged with a very thin tube passing through.
First we weighed the tube, then then teacher put the tube onto a pump system and sucked the pressure down to a near vacuum through the pipe in the end. He sealed off the pipe and we weighed it again... the weight dropped by, IIRC, about a gramme. Then he carefully released the seal and we could hear the air hissing as it got sucked into the vacuum. It took a second or two for the scales to stabilise, and we were able to watch as the tube gained weight back to its original weight over the course of a few more seconds.
Our conclusion was, of course, that air has mass!