Depends entirely in the property they use to create those units doesn't it? If they demolish 10,000 low end rental properties to build 1,000 high end properties, the answer seems obvious. Equally obvious, if they could create property out of thin air then more supply lowers prices, but property is finite.
If they could buy 10K on-rental-market units at an average price enough under $100K each to leave room to build luxury housing there, it would make a hell of a lot more sense to just continue to rent them.
