other car manufacturers realized that would be detrimental to their business
Ummm do they? I don’t care enough about cars to remember the details, but I’m sure I’ve heard some controversies about safety for at least a couple of brands
All the other self-driving cars are still very limited in their interactions with the real world. Only allowed in very limited locations and on predefined routes.
Tesla is the only people running self-driving car tech in the wild as far as I’m aware.
Level 4 exists in the form of Waymo, who operate on roads with shoddy regulations (random US municipalities), so probably not proper Level 4. Also exists in Japan, which does have proper regulation but from what I know it’s still a pilot.
Level 3, conditional automation, is becoming quite standard in the upper market segment. Things like traffic jam assist: You can actually take your hands off the wheel and eyes off the road, when traffic clears up the car will alert the driver to take over again, or, that failing, pull over on the shoulder and presumably call emergency services.
Tesla’s stuff is Level 2, needing constant monitoring by the driver.