Not every human driver can solve every situation that the best human driver can solve. Also, the most dangerous situations happen at high speed, which humans aren't great at handling unless we've had a lot of training. The main reason I'm optimistic about autonomous cars is that a system like Waymo's will only get better and better over the years. And newly produced cars will be just as good as "experienced" cars.
This is a mantra from speed limit fans. There are a lot of dangerous situations happening at low speed (bicicle coming from left in an intersection, children playing )
...that makes the human driver, who normally would get say 10k miles of practice every year will drive... 500 miles on average.
It really does need to be "car can do all of the driving", or else it will be putting people that have zero practice in those hard situations it can't handle.
LLMs are so good because they have almost the entire digitized text output of humanity available for training. They may not always provide factually correct information, but it is dished out in near perfect English (or whichever language you prefer).
Personally i think if we want to recreate a human driver full AGI is needed. But, in the right conditions current autonomous cars will work well. They just need some external helpers, like being geo-fenced to a set of roads which have all the correct sign posts and markings.