Autopilot in the Tesla Model 3 (or Model S, Model X) is not the same as the new Cadillac Super Cruise in the CT6 model.
In the case of Autopilot, it can be engaged on a broad spectrum of roads and offers things like lane change. However, the freedom makes the system sometimes not capable of handling a certain situation (see how the Model 3 struggles on the wide lane). Anyways, Tesla cars are promised to be hardware ready for full autonomous driving and should continue to improve with new over-the-air updates.
As for Cadillac Super Cruise, the system is very conservative and limited to only major highways, without intersections or even roadwork. Unlike Tesla, Cadillac uses eyes tracking (even with sunglasses) instead of asking you to keep your hands on the steering wheel. In effect, all you need to do is watch straight ahead and enjoy hands-free driving, which is apparently more relaxing, according to Edmunds. The steering wheel on the CT6 with Super Cruise is special too, with an LED indicator that shows system status.