https://en.wikipedia.org/wiki/List_of_aircraft_hijackings
Plane hijacking has been on its way out anyway after the turmoil of the 1970s. And that has probably more to do with a) the relative political stability of the post cold war period, and b) a general sense that airplane hijacking isn’t actually that likely to advance your political goals. If you read the list above, you see people hijacking planes all kinds of dumb methods, hardly any of them involves carrying an actual bomb onto the plane.