You say "just" 15 years, but Waymo is still only available in a few cities. That seems more like a slow, cautious rollout to me, not a fast takeoff. Society has had a lot of time to get used to (and tired of) the idea and come up with regulations.

My guess is that the deployment of other types of robots will often be a similarly slow grind.

That's unlike the Internet, smart phones, and coding agents, which got user adoption at a much quicker pace.