I would have to disagree on it taking that long (as in so short) - not the change to zoning law, but the actual existing building infrastructure.

Cities are one thing, and often have better infrastructure in place (though absolutely not a guarantee), but general suburbia you wouldn't find much shift in a short time. For one, availability of sites for new construction, and two, its the most likely place for quick capitalist change (new expensive clothing store rather than say, a small grocer).

Its going to get harder the further rural you get, there is more space but won't be as much appetite. Small businesses had already been squeezed out by the likes of Walmart and their ilk, and wouldn't sensibly be able to return without other changes (like being low cost enough and affordable to the local folks to go there instead of a Walmart Super Center or whatever those giant warehouse mini mall ones are called), which means financial incentives and lower and middle class folks having more money to spend.

Which you'd need to start having people stay more local for work to grow the local community.

Its a part of a solution, but it isn't a solution by itself IMO. And its going to take time to have an impact. Time that will be on a decades-long scale, considering many towns have been around for a hundred years or more that isn't a staggering timeframe, its sensible.

It definitely can't be done in the same kind of timeline as bike lines and bus infrastructure.

(Edit: stupid mobile keyboard)

I'm not, I just don't think there is that much by comparison to the huge swaths of the rest of the country.

For the record, I've lived in city, suburb, and more rural, and have spent long periods of time in really rural (like a town of 200 people that my mom has family in, and a not-even-a-town where its just 50+ acres of woods between everyone's home and its only 20 minutes by car, on roads with no speed limit, to reach the highway).

The time scale for those sorts of changes is long, and need other changes to make it work.

People really gotta start saying what they mean by "density", because I've had 4 people in 700sqft, and cannot imagine people actually want to live like that.