Jason's accident was a classic high side. If you don't know what that is, a low side is when you lose traction and the rear end goes out from underneath you and you fall on the low side.
A high side is when you lose the rear end and the rear tire bites and launches you in front of the bike. Having the bike catch up to you is never a fun experience. It might or might not catch you.
The parachute guarantees the bike will catch up to you.
Even if you miss the bike, the landing from high altitude is going to break things. The MotoGP guys break bones all the time. The parachute won't help that. BTW, I don't see the MotoGP guys wearing them. Hey Ratliff! Spend some time over on the MotoGP side convincing them of the error of their ways.