The point I was attempting to make is that we have and use the tools to control the quantity of rental housing available. Using those tools has not made renting as cheap as owning. Those tools generally help accomplish the opposite. With that in mind, there's perhaps cause to question if "controls over how many" that yardstick suggested will accomplish their aim.

So yes, you're absolutely right, technically true. In practice, they fundamentally don't do what the user wants them to do because that's not what caps are capable of doing. The tools don't work that way.