Renting these houses is obviously a lot cheaper than buying/carrying them.
However, run the numbers to determine the market size. If a renter is willing to pay up to 40% of take home pay to rent, 3k$/month would require the renter to take home over 7.5k$/month– or a salary of at least 100k$/year. Rent payments of 33% of take home pay pushes it even higher. This is without the interest deduction for people whom the interest deduction actually matters.
I find it hard to believe that there is a large market of people earning six figures who are renting. Admittedly, a lot of relatively well-to-do people have moved to the sidelines in this real estate market, but 3k for rent still strikes me as a lot.