When you ban "speculation" on an asset class, you're just telling owners (including creators) of that asset class that they will make less money if and when they sell.

Setting aside the "I know it when I see it" definition of speculation used by most people that changes as needed during a discussion and all the negative side effects that come with that, is telling people who produce a scarce asset that they will make less money when they sell it a good idea, or a bad idea?

Why do you assume that prices increasing faster than inflation is manipulation, and what is the definition of "normal changes in demand"?

Real estate historically hasn't appreciated faster than inflation over time. Supply constraints, historically low interest rates, and a couple other factors have changed that in a number of areas in the last couple decades, but not all. The Rust Belt is a prime example, yet for some reason that isn't relevant in these discussions.