So this stood out to me in the article.
“Two people familiar with the situation, speaking on the condition of anonymity because of the ongoing investigation, said the pilot of a military jet that scrambled to intercept the plane saw its pilot sitting in the left seat
slumped over to the right.”
Being able to see into the cockpit stands out because if true this is different than what happened to Payne Stewart where the intercepting pilots reported that the windows were opaque as if covered from the inside with ice.
Again it’s all speculation at this point but maybe some kind of pilot incapacitation like a heart attack perhaps? Maybe not a pressurization issue at all?
Speaking of the pilot, he was 69 years old and retired from SWA after 26 years.