If you could get all cities to build more housing simultaneously then you’d be in great shape. The question is: how do you do that? Most of the biggest problems facing humanity are coordination problems. The answer to all these problems can’t be “everyone should just do X.”

In reality, your best hope is to get one city to build a lot of housing. Then everyone moves there and we’re all unhappy.

This, by the way, is the reason homelessness is so bad in San Francisco despite their government spending enormous amounts of money fighting homelessness. All the other cities in the US sent all their homeless people to SF!

It's going to happen in fits and starts and not all at once everywhere. But there's also something of a ratchet effect as places copy what's working in other places. And no one reforming because they're all waiting would be catastrophic.

And really, not everyone is going to move somewhere. You could not pay me enough to live in NYC or San Francisco. People who love NYC would probably be bored in my small city.

Burdensome parking mandates are being eliminated or reduced across the country, as one example.

One way to try to get more places to reform on a similar timeline is to join a nationwide group, like https://new.yimbyaction.org/ or https://welcomingneighbors.us/

What is different between building more housing and building more highway lanes?