There's a lot of appeal to a car vending machine if done right. Like, if I could plug in that I want a Prius Alpha dropped off at my door for no more than X dollars, and someone would hook me up with a well-vetted second-hand Alpha, I would totally be very happy with that instead of guessing and wrangling.

The problem is that involves a lot of stuff that self-styled hyperscalers are garbage at: quality checks, human interaction, and such.