I live about five kilometers from the office and ride my bike. I pay about twelve Euros per square meter rent. My apartment even has a big yard, I just have to share it with the other tenants. A grocery store is right across the street. The next one is ten minutes walk away.
Live can be pretty nice if city planning isn't completely screwed up.
Mountain View looks like a small town in order to protect the habitat of a burrowing owl.
There's always some reason not to densify where people have already settled. We sprawl because it's the only thing we can get away with.
It doesn't have to be Manhattan like densities either. Many German cities, for example, are full of 4, 5, 6 story buildings. Dense enough to support frequent transit and common enough to not have astronomical rents.
It sounds like it just increases their health risks and lowers the quality of their landscapes over those other options.
In practice, I think you're likely to eliminate people's current perfectly good option just to lift public transit from abysmal to mediocre. It would depend on the proposal.
Rich urbanites having ugly roads in their field of vision is not remotely comparable to middle and working class people having to move in with roommates or triple their commute times.