...why is everyone's immediate answer to everything "it must be 3rd party programs!" with a very heavy and negative connotation like action should be taken?

Provoke is extremely obvious. all 23 other people can see it, and they often do. Most cases of "can you stop using provoke" come from someone else before the MT.
The animation is obvious. The boss physically turning and spinning is obvious. The target of target changing is obvious. Either someone used provoke or the tanks are fighting for aggro- and you'll know it was provoke because that boss wont be ping-ponging with that *slight* aggro lead.

provoke isnt even the only skill that does this.

you have been around since 2015, OP. im sure you've seen, i dunno, a doton placed down on single target? Perhaps you've seen a leyline. Maybe you heard someone opening a soda can and knew instantly some BLM somewhere used foul. You probably heard loud abrupt screeching and knew a SAM was close by- oh! thats an iaijutsu. You've probably witnessed a bahamut or pheonix by now. Maybe a DRG's tether launched into the stratosphere and you knew they used "jump". going back to NIN, has there ever been ANY jokes about rabbiting?

Did you need a 3rd party program to figure any of that out?