I'd say it won't happen again because the hijackers shifted the paradigm. Hijackings to that point mostly resulted in passengers surviving. It happened with some frequency in the 80's for those old enough to remember (everyone on those planes for the most part) and the conventional wisdom was to not resist as that was a generally successful strategy to that point.
The organized resistance on Flight 93 came after they started learning what had happened with the first three planes. With mad respect for their heroism that day, I have no reason to believe that the same attempt wouldn't have been made on any of the other three flights had they been 4th and the passengers started finding out what was really going on. Keep in mind that it was about 30 minutes from takeover of 93 till they started their attempt to take back control.