Welcome to the Wacky World of Unintended Consequences.
Rent controls and other legislation intended to protect tenants frequently have the effect of reducing the supply or rented property, and driving up rents.
Legislators tend to forget that landlords are not a charity; they are in it to make money. As such, they have to recoup the cost of buying and running the building plus a bit over, otherwise it is just not worth while. When you look at the total lifecycle of a habitation, buying must always be cheaper than renting. Of course, taxes like stamp duty and CGT (especially) just put up the cost of renting.
When I was doing contract work around the country I worked out that if I could see myself 2 years ahead, then I should buy rather than rent. That would cover the overheads of the actual purchase & subsequent sale. Students are typically in it for 3 -4 years, so buying should always be the preferred choice. Yes, I know about having enough capital for a deposit etc etc etc.