I sympathize with the sentiment of making flying more exclusive. But to the extent that this does not happen and instead the Majors offer self-defense training: like any other skill this needs to be ongoing. You do not take a few courses in “self defense” and you’re good! As pilots we’re compelled to at the very least to get together with a CFI every two years for a sanity check and flight review. Within that interval we had better have practiced our skills lest we be rather embarrassed when that flight review comes around. What are the Majors doing to keep their FA’s self-defense skills refreshed?
In a former life I trained with a wonderful “Sensei” (teacher) from whom I earned black-belts in two styles of karate. But that was several years ago at this time. If I were confronted today, the skills that would come out would be those that I practiced the most: nothing at all fancy, a block, kick, punch, all from reptilian muscle memory, which again was obtained through much repetition.
IMO the advantage that pax have these days is that on any average flight, there will be a cohort of folks who will stand up and oppose a person or maybe a group who are acting out. IMO our collective safety as passengers is better assured these days vs. 9/11 and prior b/c a lot of good people are not going to remain seated and and let one or perhaps a small group of bad actors take over a flight.