"Complaining," as you put it, gets people thinking and talking about the issue in a general way, and it doesn't necessarily take that many people doing so to create radical change in municipal governance. There's potentially a large constituency that's fine with seeing more multifamily structures and on board with supply-and-demand market dynamics, but doesn't necessarily know or care about their municipal regulatory regimes until the impact is explained. Activating these potential pro-growth voters is a worthwhile project. It worked on me.
Anyone who has the means to create a bohemian utopia generally has no need to do so.
> If you grew up there and feel sad that you can't afford to anymore, then recognize that property rights exist to give the owners priority access to land so anyone who doesn't obtain property ownership has to expect that one-day they'll be forced out.
That's...kind of an oddly circular argument. "If you don't like the situation, recognize that the rules are set up to reenforce the situation."
People complain because they work low wage jobs in the city and need a place to live. If they don't have an affordable place to live they won't be able to do the work that needs to be done.