Be real careful to watch the number of days these rentals are on the market. I started renting in March and have recently helped a friend rent and quickly noticed some of the exact same rentals from when I was searching with lowered pricing on some. That’s a long time on the market for a rental. There are many people who absolutely can not afford to have their home unrented for more than a couple of months.
I believe many people are new to the rental market for their property (more out of necessity rather than desire) and are either unclear of what reasonable rents are, or simply can’t afford to lower their rent due to such a large servicing cost for their property. They can ask for the rental price all day long, but rents are much more closely tied to salaries than mortgages and as was mentioned previously, there is absolutely no financial incentive to getting into a larger rent payment than you are comfortable with (unless you use your home for very important business meetings, but good luck finding THAT renter!)
I don’t really believe that the rental market can be pushed up anywhere close to covering the mortgage costs of recent sales. There are currently forces on both sides of rents and even if the side pushing up wins, the rate of increase will always be measured.