Telsa told everybody 10 years ago self driving cars were a reality.
Waymo claims to have it. Some hackernews comenters too, I started to belive those are Waymo employees or stock owners.
Apart from that I know nobody that has even use or even seen a self driving car.
Self-driving cars are not a thing so you can't say they are more realible than humans.
I've never been in a self-driving car myself, but your position verges on moon-landing denial. They most certainly do exist, and have for a while.
Yes, they still need human backup on occasion, usually to deal with illegal situations caused by other humans. That's definitely the hard part, since it can't be handwaved away as a "simple" technical problem.
AI in radiology faces no such challenges, other than legal and ethical access to training data and clinical trials. Which admittedly can't be handwaved away either.