Waymo cars are new. Wait until their fleets are 10+ years old. They'll have all the same bad maintenance issues that airplanes, semis, rental cars, and any other company-owned vehicles have.
People aren't on the whole suicidal, they're not going to go up in a plane they expect to kill them, but they absolutely will push their luck in privately owned planes and statistically that doesn't end well. Go see the figures for yourself, inadequate maintenance isn't first on the list for why GA crash rates are too high, but it's on there.
Alfred Gilmer Lamplugh