It's just like technology: If you make it happen, it will happen. If you don't, it won't. Some people are working hard, developing the technology, while many sit around saying it's impossible, etc.
Opportunity knocks, right now. There's no guarantee of success. Let's go!
"Do it the way we want or die" is a pretty bold take.
Are you going to enforce this or demand to have law enforcement or even military units do it?
You'll notice the loaded language used in the title of the article: "California's future depends on how leaders rebuild". Ideally I would think that the landowners should have priority in deciding what is built on their land. After all it is still at least nominally their private property.
Expect further arguments towards a subjectively perceived "greater collective good" to follow from that point. After this is established, the ends justify the means. In this case, the above poster explicitly describes the means as "men with guns".
That's a myth / fantasy of gun and violence zealots and anti-liberals.
Obviously, to scholars and to anyone looking at the world, the basis for governance is consent. There are not enough guns in the world to do it otherwise. And I've never and I don't know anyone who has ever done something because the government pointed a gun at them. They did it because they are law-abiding people, social beings, and want a fair, ordered society.
For governance, perhaps, but not for government.
A trivial example: I do not consent to the authority of my city, county, state, or country. I have withheld that consent my entire life, and yet all those levels of government continue to not only exist, but to grow.
There are many examples of places around the world who managed to intersperse SFH with medium-density housing (3-4 stories apartment buildings) so it's not an either-or situation. For example: many suburbs of Stockholm have developed this way, it allows options based on people's budgets and needs, while also creating enough density to attract local businesses so people are not entirely car-dependent for basic necessities, creates third places for meetings, etc.
I'm preaching to the choir though, I do understand you will probably never understand or see it that way given the vitriol you started with. It's quite sad because there are other ways for a community to live that can cater to different needs where mixed-housing exists while also making these neighbourhoods more interesting and livable in themselves.
The city could issue no permits to rebuild SFH on that land and then buy it for 15-minute walkable development.