I suspect you are being down-voted because a lot of landlords are renting out their first home while they have moved out and into a newer, nicer home and are now just exploiting the underclass.

Presumably the mortgage on the first home is quite far below current market prices, but this is not enough to drive the landlord to offer a price that is necessarily in line with rents at the time the home was purchased.

The mortgage interest is no longer tax deductible, so effective cost of ownership is higher than when compared to someone paying a mortgage on a home they live in.

The profit from renting is compared against profit from selling. If the rental price is driven too low, the owner will prefer to sell and collect the profits (and the home will likely be taken off of the available rental inventory, which will further drive up rents).