Plus also, you have to be really pretty rural before you can't get things delieved.
You don't have to be very far before it becomes much more expensive, though. Since I live in a crappy little county with a crappy little retail store selection, I can only have most large things shipped to a freight depot. Some people will ship them to the foot of my driveway, but they can't get a big truck up it.
This is not about me, though, this is about the city. And if you seldom leave it, and you happen to live where you can walk to work or where public transportation works for you then yes, it surely makes sense to have no car. In a lot of cities, it's not reasonable to relocate to be closer to work — finding any housing at all is often an epic struggle. So we're going to need either to fix that problem, or to build public transportation systems which actually let people go where they need to go in a timely fashion. For example, it has to be faster than walking. Certainly in San Francisco that is often not the case, depending on which boroughs you're traveling between.
Even with the rentals, I spend much, much less per year than I would on maintainance, insurance, road tax etc.
In the USA we pay the same road tax regardless of whether we own the vehicle. Our registration fees only pay for... well, they don't apparently pay for much of anything actually. But that's another rant. EVs will cut maintenance costs. Insurance is based on the number of miles driven.
And, I can also rent an appropriate vehicle for the journey, like a nice long wheelbase transit if I'm moving big things or a normal car for simply getting me somewhere.
If you're commonly making trips which can be made in a total econobox then that can be viable. If you are commonly making trips which require a larger vehicle, that becomes prohibitively expensive in fairly short order. I, for one, am two meters tall, and I always require a larger vehicle. Only a very few mid-size vehicles are even large enough inside to accommodate me. Nissan and Subaru are the only Japanese manufacturers which leave enough space for a human of my dimensions, for example, in anything other than the largest vehicles from a luxury sub-marque. In Panama I was able to rent an Almera (Sentra) at one point and that was not great but okay, but then I got stuck with a Yaris later and it was a knee-cramping nightmare.
There are lots of considerations which might lead people to need to own a car even if they live in a city. Most of them could be eliminated by implementing elevated PRT, for those people who tend to stay within its borders.