> What’s the end-game?

Step 1: Move somewhere affordable.

Step 2: Spend years building an awesome community because you personally endeavor to make it what you want.

Step 3: Profit.

Notice this is the same process for a fixer upper house. It's just a buying into a fixer upper community. Labor intensive. Higher variability in the outcome but notice much more upside than flipping houses.

> When does growth stop ? What’s the end-game ?

Why should the growth stop? People are clearly demonstrating a desire to move to these cities. I see no reason why NIMBYs should be allowed to artificially decide that newcomers are not allowed. Growth will simply continue as long as people keep moving in.

> People are clearly demonstrating a desire to move to these cities.

Yes, they demonstrate a desire to move into these cities in their current non-hypergrowth form

Then you follow up and make that desire a reality by putting a down payment on a property

Talk is cheap

I think humans have demonstrated time and time again that densely constructed cities are a desirable place to live. Are there some people that would leave if these cities started loosening zoning and allowing dense construction? Sure - not everyone wants to live in a big city. But I would argue that the net change in population would still be massively positive.

Besides, why should existing homeowners get a monopoly on deciding what kind of city Santa Cruz should be? If there is a desire for dense housing, then dense housing will get filled. If you're right that people moving to these cities want suburbia then one would expect new multi-story apartments to go empty. But that's clearly not what happens.