Why does everyone assume the cost will decrease with scale? How many people can afford a Tesla right now? Let alone a fully autonomous car?
If flying were more affordable and less strict more people would own their own plane. It isn't and they don't. I see self-driving cars a lot like airplanes and John Deere tractors. That is, expensive proprietary tech that you have no control over. No thank you.
Why does everyone assume that most people want to share a vehicle?
Because you don't need to own the car - you could feasibly rent one on demand (like a taxi), since you can now rent a car without the necessary wage overhead of the taxi driver, or the minimum costs of car-rental (i.e. car rental typically is per-day, for logistical reasons) or the logistical problems of car-rental (i.e. you need to drive to and from the car-rental place, to pick up and drop off the car - and by "drive" I mean "get a lift or use public transport").
Plus, the self-driving stuff shouldn't be particularly expensive, and will be counterbalanced by lower insurance premiums, and likely tax incentives once voters realise that they really do save lives.
"Why does everyone assume the cost will decrease with scale? How many people can afford a Tesla right now? Let alone a fully autonomous car?"
Because just about everything decreases with scale, and it's not inherently hard tech. Tesla's main problem is their lack of scale. As are autonomous cars.
"Why does everyone assume that most people want to share a vehicle?"
Money. It's not "want", it's "can tolerate so as to save money". Your car, when adding together all the costs (purchase, fuel, rego, maintenance, interest payments if you borrow instead of buying outright) is one of the biggest expenses that most people have. Sharing a car between several people should decrease the costs by an order of magnitude, which could be used to buy whatever people spend their money on these days, or saved.
Let's say each ride cost $10... that is $20 to $40 per day just for the kids on most weekdays. Add in birthday parties, saturday games, doctor/dentist, trip to grandma/grandpa that live 7 miles away... and we are talking $1000 per month in "ride-sharing costs" for my children alone. We could add in my wife and I's costs, but it would be silly.
Maybe this service is less than $10 per ride, even at $5 per ride it is wayyyyyy more expensive than I currently spend on a 4 year old Toyota Highlander with low miles with insurance and fuel.
a.) Snacks and supplies in trunk - lockable containers inside. All could be accessible via app/key fob only.
b.) Who says the suburbanite your renting to won't want to use a car seat?
c.) Camera, ID, cleaning deposits, car self-drives to detailer on your lunch break.
$1,000 a month is a heck of a carrot to keep a car clean - even if that's not for you is your worldview really so small that you cannot imagine it being for someone not all that dissimilar from you?
If the total cost of ownership is, say, $1000 per month, you might only pay $200, or about $2.20 per ride.
Why? We literally never see that with top shelf products. This isn't an arduino solder job. This is going to be an integrated software and hardware package that will rival an aircraft autopilot/navigation. Please check you facts on the cost of these things.
I don't want walmart brand, everday low price components on my self-driving vehicle. I want top of the line if my life is in the balance.
These are all things that started high and fell low. The historical prices for each of these systems reflects this fact, as does their gradual movement through the available product line-up. They all started in top of the line vehicles that cost well north of the average person's yearly salary, and are steadily creeping into the lowliest models.
I see nothing in self-driving systems that make them special in this regard. They're already largely an amalgamation of commodity components whose prices are trending downwards.
You can bet on them staying a niche product forever, if you wish. I just think it flies in the face of historical evidence.
Google claims that it dropped the price of lidar by a factor of 10x once it started producing them. That seems like a significant, factual, drop in cost.
If ridesharing was awesome, we would see it now with luxury cars. We don't because it is stupid and will not reduce the price of the car dramatically enough to outweigh the negatives.
A lot of the regulation that drives the cost of planes up won't apply to cars because of the different economies of scale.
The most popular light aircraft in history is the Cessna 172, and since it was introduced in 1955, only 43,000 have been built. Ever.
By contrast, the most popular vehicle on the road today in the US is the Ford F-series pickup truck. Since being introduced in 1977, Ford has sold 26 million of them. So roughly 600x as many as Cessna has sold 172s over a period of time 20 years longer.
The US market alone was responsible for 17.5 million new cars and trucks being sold last year. Globally, it's approaching 100 million per year. Pretty incredible economies of scale available with that kind of market.
I'd quite like the freedom to be able to commute to work, go out for drinks with people after work and come home again at the time of my choosing without relying upon someone else to cart me around, paid driver or otherwise.
THAT seems freedom-enhancing.
Obviously, the assumption of all those involved is that the price will plummet as the technology becomes more adopted, so the goal is to get to a price point where the earliest adopters will be willing to pay. For self driving cars, talking about plumbers not buying this at the current price point is a bizarre argument.