Yes, really you haven't actually reduced demand in that instance; you've just tried to suppress it artificially. Those people are still looking to become homeowners but can't right now. It's not that the demand is gone; it's just that they cannot.
The problem is that you haven't improved affordability. The element of any house price stabilization or decline that comes from locking people out isn't affordability. That's just reducing the ability of people to buy, reducing equity for people who have houses and reducing affordability by telling people they can't qualify.
There is a better happy medium that we can find and move forward, to help people get into the market. As long as we can provide the right amount of supply moving forward, continuing to have mortgage rules that enable people to get out of rental is very good, not only for them but to open up the rental stock for other people who need more affordable rent.