Your Cessna 172 isn't doing Mach 1. It's certainly possible to open the door at any speed a light aircraft can achieve. The door/canopy my get ripped off, but that's kind of irrelevant.
That would have a 99.99% chance of killing the pilot, unless they happen to be flying a T-6 Texan (turboprop USAF trainer) or something, in which case the Martin-Baker ejection seat would help. It would be very difficult to put an unconscious pilot hooked into a tandem parachute.
I didn't get the impression that neya is too concerned about the pilot's safety, or anyone else on the flight for that matter. Seems like a solo jump to me.
Plenty of skydivers and base jumpers travel (with gear) to go jumping. The TSA might look at you funny* but there is certainly nothing illegal about carrying on a chute.
* Of course everything is always at the discretion of the TSA agent, they can prevent you from getting on a plane because they don't like the shirt you are wearing.
The article seemed more about small airplanes. Big ones have a series of people who would probably be in line to try and fly them before "random passengers with no experience". I don't know anything about planes, but "look for a parachute after you've stabilized the plane" doesn't sound like the worst possible idea, depending on the status of the pilot and other passengers.
