The root cause of the supply constraint that ultimately gives real estate it's value is the land, and more specifically, the land being in a particular location. For example, a row of condos built right next to a major employer of the town, in the center of the city. That land is going to be valuable so long as that town exists, and as the population continues to grow, will only become more valuable. Adding more houses won't reduce the value of those condos the same way that adding more lanes to a highway doesn't reduce the congestion.

The idea that houses are appreciating assets doesn't come from some fundamental law or ideology. It comes from recognizing reality. There is only so much land where people want to live, and population tends to increase (we are talking about urban and suburban areas, of course), so the demand and price increase. It's pretty simple, really.

NIMBYism, zoning laws, permitting, those are always familiar and convenient boogiemen for people who don't want to do actual analysis of market factors. But, what you are really wanting to argue against is private property ownership.