There aren't just a "few" in the Bay Area—they've become totally ubiquitous in SF.
In my opinion, it's as similarly off-base as to making claims that 'mach speed consumer air travel' "arrived" just because for a few decades you could catch a Concorde flight between NYC and London.
You’re right that they have a long way to go before being fully mainstream. But thousands of people are using them every day in multiple major cities. That’s a pretty big milestone.