Airplane autopilots follow a lateral & sometimes vertical path through the sky prescribed by the pilot(s). They are good at doing that. This does increase safety, because it frees up the pilot(s) from having to carefully maintain a straight 3d line through the sky for hours at a time.
But they do not listen to ATC. They do not know where other planes are. They do not keep themselves away from other planes. Or the ground. Or a flock of birds. They do not handle emergencies. They make only the most basic control-loop decisions about the control surface and power (if even autothrottle equipped, otherwise that's still the meatbag's job) changes needed to follow the magenta line drawn by the pilot given a very small set of input data (position, airspeed, current control positions, etc).
The next nearest airplane is typically at least 3 miles laterally and/or 500' vertically away, because the errors allowed with all these components are measured in hundreds of feet.
None of this is even remotely comparable to a car using a dozen cameras (or lidar) to make real-time decisions to drive itself around imperfect public streets full of erratic drivers and other pedestrians a few feet away.
What it is a lot like is what Tesla actually sells (despite the marketing name). Yes it's "flying" the plane, but you're still responsible for making sure it's doing the right thing, the right way, and not and not going to hit anything or kill anybody.