Great question. No strict definition as such for me, but in the context of transportation, it loosely means that it must be 'easy' for most people to get from point A to point B, using the least amount of time. Ideally it must must be accessible for all people (so teens without a licenses, legally blind people, or anyone without the means to get a car etc). From a non-transportation context (just adding, not very relevant to the answer), places with no loud traffic noise and just a nice general atmosphere of people around. Think streets with trees, and lively public spaces for people to hang out.
> If cars lead to better outcomes (and they do, once self-driving is deployed), then why not? Why force people into densified anti-human hellscapes?
No one is being forced. If anything, these measures only makes the cities with high urban density more livable for people. The 'hellscapes' have more to do with the housing crisis and zoning laws than transit infrastructure.
Idk why most people think urban density is a problem to be solved (using tech like self driving for eg), because it ultimately always circles back to the fact that density is the only sustainable way for cities to develop and grow in the long run. Even if it is not perfect.
> I fail to see anything human in dense cities like Tokyo or Manhattan.
It would be even more dystopian if Tokyo didn't have a great metro and people had to wait in traffic for hours. Imagine the increased stress, lesser free time, and lower quality of life from all the noise and pollution.
> Yes. And once people can, they opt out of transit as well.
When exactly will most people have the option to opt-out, and how likely and how exactly will it happen?
I also feel like you're arguing just for the argument's sake. If not, we probably have fundamentally different views on what's 'better' and I don't think any amount of convincing will change either of our minds.