True, and even two hours maybe pushing it. The crash in PA on 9/11 was a direct result of passengers attacking the cockpit after they found out what happened to the other planes.
I don't mean to assume bad faith, but this was, at best, a throwaway comment that minimized the bravery and sacrifice of a lot of good people. Either way, I'd like to recommend you educate yourself a bit more. The Wikipedia page has some excellent detail, and if narrative structure is your thing, the book The Only Plane In The Sky is a masterpiece on the subject.
How has this claim been authenticated?