Canada

A combination of a few million new high density housing over the next decade, a complete rewrite of zoning laws to take them outside of the hands of the cities, and the removal of any need of any neighbourhood association to sign off on any new development.

Commercial producers won't make housing cheap and affordable on their own in any reasonable time-frame. Even if they instantly become able to construct as they like, market forces will take time to let housing prices cool off.

Which goes into my second point, zoning laws as they exist prevent housing from being made in the first place. Especially single family house zones are the single biggest killer of affordable housing. People already make their houses massive, to the point that they're getting close to low-rise apartments.

Which goes to the third point: the character of a neighbourhood changes every single day, so any attempt at the preservation of such a thing is just a bald faced lie, even if they're lying to themselves saying it. The neighbourhood I grew up in were all small houses, from tiny two stories to bungalows. Every single house is easily twice if not three times bigger than the ones I remember as a child. There's no trace of the neighbourhood I grew up in, aside from the fact that they don't house any more families than before. Hell, they probably house fewer people than before as I bet almost all the families there have only one child at most.

The unfortunate result if there was actually the political will to do this is that it would cause a pretty big depression as people have been conditioned into treating housing as an investment for their retirement. A necessity of modern life being used to create profit, that in itself is a non-performing asset that adds exactly zero dollars to the economy and is worse than buying a whole bunch of gold ingots in the hopes that its value will rise faster than inflation.

Personally, I'm patient so I'm fine with house prices going down slowly, as long as rentals get cheaper. It's stupid when such a high number of young decide that they're pushing off moving out of their homes due to seeing it impossible to afford one of their own. Delaying getting a home, even an apartment, means delaying getting married, presuming you're even bothering to date. Delayed marriages means fewer children, which means a stagnating and eventually dwindling population.

If the population stagnates, then everything falls apart for the elderly as the price of everything goes up as there's fewer people to make, deliver, and serve everyday items. And that's not to mention that the entire RRSP system depends on sufficient new blood putting money into it just to maintain the status quo. Lots of retirees all over the world are going back to work only because inflation has gone up a bit. How many will do so when it becomes impossible to keep inflation in the most critical areas down due to the lack of workers?

In the end, housing is the root problem, and while I fear it causing a major recession, I still think it's preferable than for housing prices to never come down. The economy will tank in the future whether the housing bubble bursts or keeps its course. But only one of those two options gives us a hopeful future beyond that bleak one.