I'm American and I intend to do this, but it's only made feasible by moving to the Netherlands, which is much better designed.
The only people spending $10K/year on their car want to. The kind of folks who would be most swayed by a financial argument manage to spend much less. On top of that, your analysis is one-sided. What would be the going rate for additional daylight hours if I could sell them on the open market?
That doesn't even account for increased costs created by auto-centric development, which incentivizes sprawl and makes housing more expensive (eliminating parking minimums can cut monthly rents by $250 per unit because you can fit in a lot more units), roads more expensive, and even simple things like eating out at a restaurant more expensive because you're still paying for all that parking, even if it's baked into the purchase price.
It is certainly possible to have a car for only a few grand a year by buying used cars and doing your own maintenance and repairs on your own, but that comes with the compromise of decreased reliability, and most Americans need a reliable car. My own costs are probably around $5K a year because I drive a 20-year-old diesel VW Jetta, but I also don't need a car on a day-to-day basis because I bike to work.
Sure, some people might. And every little bit helps.
But car ownership rates in the US are actually increasing in recent years, despite the fact that cars are getting more expensive to own. And cars keep getting bigger, too. I just don’t think it’s realistic to expect large numbers of Americans to trade in their SUVs and pickup trucks for tiny little e-bikes.
I live near a major bike path. Every bar along it has a lot of bike parking ,but none of the other stores and restaurants have any at all, not even the bike shop. Many people drive their bike to the bike trail instead of riding.
How do we get people to ride their bikes to get groceries? They could also ride to church on Sunday, or other similar activities. These little trips need to be tackled before we think about getting rid of cars.