Why doesn't it always autoland? We already have self driving cars, so a self flying plane seems imminent.

Very different standards - in its current form of emergency autoland it just needs to be proven to result in equal or better outcomes as a plane with no rated pilot onboard; the best case is another person that knows how to use the radio and can listen to instructions but the more likely case is a burning wreckage when the pilot is incapacitated.

To always auto land it needs to be as good as a fully trained and competent pilot, a much higher standard.

We don’t have self driving cars.

Because it requires specific equipment that many airports do not have, for one. It also doesn't understand things like noise abatement procedures. It has to be setup properly. You don't want pilots forgetting how to fly the airplane. Any of a dozen other reasons.