This resolves based on my own experience of how many cars I see driving around in whatever U.S. city I am living in (or have most recently lived in, on the off chance I'm not living in the U.S.).
I will go outside to the street and wait for a few cars to pass. I will try to look in the window or look at the model of the car to try to figure out if the car is driving itself. Once I feel confident about whether more or less than 20% of cars I see are self-driving, I will resolve this either YES or NO.
Nov 2, 5:45am: Will 20% of cars be self-driving by 2030? → Will at least 20% of cars be self-driving by 2030?
Nov 2, 2:58pm: Will at least 20% of cars be self-driving by 2030? → Will at least 20% of cars I see be self-driving by 2030?
In response to a question "Self-driving" means an SAE level 3,4, or 5. The self-driving system has to be engaged though - a car that is capable of SAE level 3 but which is actively being driven by a human won't count.
@StrayClimb My intention is to go outside of whatever house or apartment I'm living at to whatever street is nearest to the front door, at whatever time I realize I have to resolve the question, and look at cars as they go past (if it's very late I might wait til the morning). I don't know exactly how many cars I want to look at yet.
The driving consideration IMO is that "cars on the street" <> car ownership by 2030. Even if self-driving cars make up only a fraction of car ownership, there could be a small number of Tesla, Waymo, and Cruise vehicles that are running 24/7 performing taxi services.
We haven't even achieved full taxi ability in SF and we are probably already at 2-5% concentration on the roads. I'm expecting that to grow meaningfully once Waymo / Cruise open up the ability to taxi indiscriminately.
Typical cars last about 8 years. So the 20% newest cars in 2030 would probably be bought some time between 2028 and 2030. Will these be self-driving? Maybe. Will people use the self-driving feature in the city? I'd guess only a fraction of drivers.
There are many unknowns here, but overall I'm leaning toward NO.
@Adam Yep, in terms of the SAE scale, it would mean level 3,4, or 5. There either has to be no driver in the driver's seat, or it has to be reasonable to think that the person in the driver's seat is not driving the car.
@Boklam I grew up in the SF Bay area, went to college in LA area. I am currently in Grad School in Urbana, Illinois. I study CS, so I consider it more likely than not that I will be living in some kind of tech hub in 7 years.