wow! I understand the guy was very emotional after this happened to him, and he is probably still being medicated and sedated.
The way you described the accident, with him being pinned to the wall at 60mph or more, I don't think anything would have saved his arm and leg.
Riding gear is excellent if you end up sliding down the asphalt at highway speeds, but it wont save you if you hit something, or are pancaked between a vehicle and something else. Everything has its limits.
The most important thing is to avoid accidents at all costs - riders wearing full gear die in accidents every year.
I had my Ford Fusion up to 100 mph on the thruway last summer for about 2 miles - the highway was empty and I wanted to see how quickly it would break 100. After I took my foot off the gas it took nearly a mile for the Fusion to coast back down to 70mph. I would never ride my bike that fast, not on the roads... maybe on a track after about 10 warm up laps.
I certainly would not disagree with the guy, its human nature to try and go back and figure out what you could have done differently to prevent the terrible thing that happened to you, but at 120mph we are like a 200 lb water balloon.
Im temped to say he is lucky to be alive, but that does not sound right. What a terrible thing for anyone to go through.