That's an interesting viewpoint; since I moved here ~5 years ago (has it been that long already?) it's always been my opinion that owning a car here was a fool's errand due to the problems with parking when leaving the house, and cost of parking when staying at the house, plus the annual break-ins etc. I do spend probably $200/mo on uber but it's a quarter of the cost of owning a car, and get around on foot otherwise. I don't typically leave the marina/north beach/fidi/soma/mission areas of the city though. If you live in the sunset that would change the equation quite a bit.
Oh I definitely agree that owning a car is horrible in SF! Parking is super difficult and when you do find a spot, it's so tight that you need to be an expert to even get in/out. I don't think there's a good option for getting around in SF. I end up doing a mix of walking, taxis (also bad), Uber/Lyft (ok) and occasionally rent a car if I'm going to be making trips to the valley (very bad).
I'm just comparing the walkability to other major cities. I find SF to be pretty unwalkable all things considered. Especially compared to European cities or NY.
The city works if you are able-bodied without kids. In that case, you walk as far as 11 miles but usually just a few miles. It also sort of works for the people with $2,000,000 single-family homes, because driving to a distant supermarket (with parking) becomes an option.
I'm by no means lazy but I found the distances between things extremely far to walk, with many large hills in the way (usually). For reference, Manhattan is only 2 miles wide and stuff to do is extremely clustered and easy to access and there's a great subway and cab system. SF is pretty abysmal for many reasons and getting around is one of the main ones.
Totally agreed that there's no place to park btw, yet another difficult thing about that city.
I found San Francisco to be very walkable, with good (not great) transit. I lived there for over 15 years without a car. I commuted for 5 years from Russian Hill to what is now Mission Bay -- walked 10 minutes to catch the 30/45 bus which dropped me off a few blocks from work. I could walk it in about 45 minutes.
When I lived in the Sunset, I took the train, and that was worse than the bus - overcrowded trains meant that they sometimes skipped stops. So I usually biked instead.
The city is just not that big, most places are within walking distance if you're not going to/from far-flung areas of the city -- you can walk from the Marina to the Financial District in under an hour. (but the 30X made it a tolerable commute, usually under 30 minutes)
It probably depends on where you live in SF. I was on the border between Noe and Mission. I lived there for a decade and found it very walkable. I owned a car but drove maybe once a month. I had good produce at corner stores (both Asian and Mexican), a butcher and seafood store in walking distance. Nice restaurants and parks in walking distance. I took BART downtown to work. Sometimes went to the ferry building. There was a summer farmers marker a block from work and dozens of restaurants in a one block radius. (We moved for more space and better schools.)