Not at all. Small towns and cities have been pedestrianizing a few key blocks for years.
In the case of Denver or some place like it, do a few blocks around the light rail stations. The car owners won't really notice (yet), but the small businessmen will complain. Ignore the small businesses, they are wrong about their own situation: Foot traffic will more than make up for any lost parking.
In fact there is a name, https://en.wikipedia.org/wiki/Tactical_urbanism, for this sort of bootstrapping, to build a loyal constituency over people defending their new car free privileges rather than merely imagining an alternative future.
This sounds wonderful. I would love to live somewhere like that. Cars suck to be around and having a massive boulevard all to yourself to walk down is a fantastic feeling. I'm not sure Tactical urbanism will be enough to overcome the problem you identified above.
I mean, America is deeply behind and I'm not sure it can be reformed. Maybe the best thing to do is move some place that does it better and hope to help set an example, I'm not sure.
But stuff like congestion pricing, the 14th street bus lane, and bridge conversions, in NYC gives me a little hope. Manhattan can also set a better example for the rest of the US --- active measures rather than simply basking in good decisions made 100 years ago.
In the case of Denver or some place like it, do a few blocks around the light rail stations. The car owners won't really notice (yet), but the small businessmen will complain. Ignore the small businesses, they are wrong about their own situation: Foot traffic will more than make up for any lost parking.
In fact there is a name, https://en.wikipedia.org/wiki/Tactical_urbanism, for this sort of bootstrapping, to build a loyal constituency over people defending their new car free privileges rather than merely imagining an alternative future.