Ah, the good old ad absurdum.
These companies literally hail themselves as "future of transportation".
> A hypothetical applicable to every mode of transit, private and public.
These are private companies looking for profit. These are not hypotheticals given what is happening to other cars and car manufacturers.
> Also, you're the one who originally argued these services' "entire social context is 'never encounter another human as you go from A to B'."
These are literally robo taxis. A taxi is literally a car that is taking you from A to B. And they are also removing the driver from them. Oh, and don't forget the existing of things like Boring Co. which exists almost solely to undermine public transport.
Their intended future is nothing but endless roads with isolated vehicles going from A to B. There's no other "social context".