Sitting might be a requirement for you, and it's fine, but should also be willing to pay the price for it, i.e. live in a suburb that can accommodate your preferences. You cannot live in a dense city rich in amenities and expect to be sitting all the time, it just doesn't work geometrically. In many cities (granted, not San Francisco), people happily stand in public transit for the dozens of minutes they have to spend there, and have satisfied with their experience. Go to Zürich for instance, you'll see bankers riding the S-Bahn when they could afford a car.
Yes it does! I UberPool to work quite a bit, and have not poofed out of existence by participating in a geometric contradiction. You are claiming that we should ban something that currently works; "it doesn't work" is nonsensical as a supporting argument.
>people happily stand in public transit for the dozens of minutes they have to spend there, and have satisfied with their experience.
In many places, people happily go without basic medical care, electricity, or indoor plumbing. All of these things are terribly expensive and somewhat environmentally damaging, people who lack them are still happy, so... let's ban electricity?