This does lower housing costs though. Somebody who makes a lot of money can live there. If these units were not built, you would be competing against those rich people in the rental market. Your landlord chooses not to renew your lease so he can give the apartment to Mr. Moneybags, and you need to go live somewhere else.

Less competition among renters is always good for renters. Just because these particular units are expensive doesn't change that.