Packing your liquids, there are never any bags, or any staff who might direct you to some, you have to take off your shoes for reasons apparently, and then the bathrooms. Piss everywhere, no locks on any doors, sinks full of snot from people blowing their nose, broken soap dispenser, and piddly little tap so short you have to touch the filthy bowl to get a dribble on yours hands. Then the self checkout starts SCREAMING at you, SCAN ITEM TO BEGIN TRANSACTION. Fuck you, leave me alone. Don't get me started on the crowding.
All of the above applies to every form of public transport.
Edit: I had forgotten that once you are on the plane they spend the first hour screaming at you with announcements at max volume.
TSA are all power-tripping assholes, fuck them, amen on the bathrooms too
But my hyperfocus since I was a kid was in aviation, so now I'm at an airport basically half of my waking hours. But I love my job (the button pushing part, not the employer part) - so it's very contradictory.