I'd wager most people, when talking about a plane's autopilot mean the follow waypoints or Autoland capability.
Also, it's hard to argue "full self driving" means anything but the car is able to drive fully autonomously. If they were to market it as "advanced driver assist" I'd have no issue with it.
What Tesla is (falsely IMO) advertising as "full self driving" is available in all new Mercedes vehicles as well and works anywhere in the US.
Mercedes is in the news for expanding that functionality to a level where they are willing to take liability if the vehicle causes a crash during this new mode. Tesla does not do that.