> Raising taxes on these people is not going to change their behavior in any meaningful way. A few extra cents, or even an extra half dollar is gas taxes is going to be a lower cost to them than uprooting their life and moving within biking distance.

GP said EU levels, so it's not a few cents or "even" a half dollar. It's straight up doubling or tripling gas prices. This would no doubt impose a lot of hardship on people, and there might well be significant political upheaval in the process, but if you think it wouldn't change behavior and the suburban sprawl problem then you don't realize how inelastic people's income really is.