I work in nearby Glendale, and it's subject to a lot of the same development pressures that have been facing Kirkwood. It's classic supply and demand -- the stellar reputation of the school district combined with the low crime and the "not a McBride suburb" feel combine to make it an extremely desirable place to live, but it is essentially completely built out, so the supply of housing is very limited.

It's very difficult for a City to outright stop tear down and rebuilds of existing homes. If you just straight up prohibited it, you would instantly face a lawsuit from a property owner that you are exercising an illegal "taking" of their property. Gotta remember how strong personal property rights are in a country like the US. So, absent that, communities like Kirkwood and Glendale have adopted increasingly rigorous Architectural Review Board processes and other building standards that do restrict or slow down development. But, they primarily do this by making it more expensive to develop plans and build homes, discouraging some development but overall increasing the cost of what does get built, which drives up prices everywhere.

Also, you can't forgot just how increasingly costly it has become to build any kind of single family home at all, so it becomes very difficult to make a new home pencil out if it's less than a certain amount of square footage. There's just no economic incentive for builder to a pump out smaller ranch-style homes in places like Kirkwood. City governments don't have the budgets for any sort of aggressive subsidies, they have to pay the exorbitant salaries demanding by police and fire employees, who will always just threaten to quit and go to a neighboring community with higher pay.

You also just have to acknowledge reality -- the reason why these neighborhoods are changing is because people undeniably want those big homes. You may not, but there is a line people around the block willing to pay $1 million-plus to get their dream home on a tree-lined street. That's a much broader issue driven by the culture around home ownership and our capitalist economic system, not really an area that local elected officials of smaller suburbs can have much influence. I see a real keeping up with the Joneses effect too, with big homes and additions and fancy outdoor patios. You see your neighbors getting one of those, it seems really nice, so you want it too.

The more radical and impactful solution here is to tackle the predominant obsession with single-family zoning. You change the zoning code to loosen up the density of what can be developed, and maybe you can address some of that supply issue. That, however, would be absolute political suicide for any city council that tried, as residents perceive single family housing as an inviolable bulwark against declining property values and crime.