Yes they have.

Tesla Autonomy Investor Day 2019

https://www.youtube.com/live/Ucp0TTmvqOE?si=blLBL58Qv_qjwcAn

At 3:13:41. Robotaxis is clearly written on that slide. Elon Musk is talking about robotaxis for minutes as well during the official presentation to investors.

I suppose you could argue that as long as the car is doing the driving, it is in fact full self driving, even if you have to watch it?

No, you can't argue that. No reasonable person would see "full self-driving" and assume it means they have to watch it like a hawk instead of taking a nap or watching a movie.

Well, at least no reasonable person before Musk had normalized this garbage.

My (non-Tesla) car has adaptive cruise and lane-keeping, and it works quite well. The car is certainly "doing the driving" to some extent, but "full self-driving? No, definitely not.

It’s not “full”, since it only works in very limited circumstances.

By that definition any car with cruise control is “full self driving”.

I don't have a dog in this fight, but cruise control doesn't turn off the highway, drive down surface streets, obey streetlights and signs, and navigate you home on its own.

Cruise control only manages the speed, right?