Because a single autonomous vehicle operating in a shared
    fleet can replace multiple privately owned cars, the
    widespread adoption of this technology can’t help but
    reduce new-car sales volumes.

If we can travel and send stuff around from point A to point B cheaply and instantly by dropping ourselves or an item into an ocean of cars roaming our streets autonomously, there is a lot more demand for rides.

Also comfortably traveling longer distances might alter where we live. If we can walk out the door, sit down in a comfortable robotaxi right away and exit in the city center 10 minutes later, we might not have to live right in the city center anymore. Another driver for more demand.

I doubt that here. Cars are already near saturation, at least in the US.

Essentially everyone has a car. The car is mostly idle. If car availability starts to approach instant then people don't need personal vehicles that are idle 95% of the time. Car quantity overall goes down unless you can 20x current utilization, which is a lot of trips and fuel.

Not to mention that if anything resembling current quantity of extant cars becomes the current quantity of cars using roadways at a given moment, most cities will gridlock.

If the thesis is "cars will approach 50% or greater utilization" then car numbers must drop barring a massive increase in road capacity for which the land does not exist.

> Also comfortably traveling longer distances might alter where we live.

You mean like last time? More cars being the answer to problems created by creating too many cars and reasons to use them is like more people buying guns to counter the gun problem, and I can't think of better "tragedy of the commons" applicable situations.

As I start to get older and I spend less and less of my time in the deep suburbs, I'm starting to be more aware now of the phenomenon for people to get less social and less trusting the further away from a core area (or, arguably also the ground in the case of skyscrapers, but much less so) they live. I don't think it would be a net win to hypothetically encourage further dispersement from one another.

> No mention of Jevons Paradox?

I wish HN commenters would stop bringing up Jevon's Paradox:

1. We see it mentioned all the time now, i.e. When AI makes producing software essentially free, there'll be more jobs. As HN has maybe 75% of the frontpage filled with AI stories, it means we see it almost every single day!

2. It essentially describes outliers. Driving food costs down to a fraction of the peak price (basically down by 90% over the last 200 years) did not result in correspondingly higher food consumption.

3. It only applies when the market is not yet saturated. Making cars more fuel efficient (by going EV) in the last 5 years did not result in correspondingly more miles being driven.

Any time you feel compelled to bring up Jevon's Paradox, ask yourself "Are we talking about energy here?" and if the answer is "No" then it probably doesn't apply.

Keep in mind that even if Jevon's Paradox applies, it does not mean that the society actually benefits. If you drive the value of all human labour to almost zero, you can't use Jevon's Paradox as an argument that the increased efficiency means that we're all living a life of leisure.

Where do the cheap cars come from? Fuel and electricity aren’t free

This is the dumbest possible approach.

We don't need fleets of autonomous vehicles, each carrying two tons of metal for transporting a person or two and clogging up cities. We just need a train network that doesn't suck.