I remember for years people on HN said Uber would never work as a profitable business because it spent a lot of VC money earlier on without having enough revenue to cover it all. It's been around for 16yrs now despite running in the black until 2023.
Waymo has ~1000 cars. Uber has 8 million drivers. Worst case Uber will be acquired or merger or make a deal with one of the many AI driving startups.
I predict Waymo will have their own struggles with profitability. Last I heard the LIDAR kit they put on cars costs more than the car. So they'll have to mass produce + maintain some fancy electronics on a million+ cars.
