Outside of a limited set of legitimate interests, government functions in publicly-owned airports are generally open to filming. Passengers can’t pass through TSA checkpoints without a ticket or other authorization, but prior to the checkpoint it’s generally not a problem as long as the activities don’t interfere with the function of the airport or screening activities.
To be sure I wouldn’t want to be filmed in my workplace either. At the same time without documentary evidence of bad actors, a passenger likely has little recourse against TSA or airline employees who treat them poorly.