Those marks are still used in many places to deny would-be renters a place as they are deemed 'insecure' by the landlords. At that point, it is effectively "unaffordable" as the supply is artificially staggered and the minimum to enter is higher than the market would dictate otherwise. Most could make it work and still have room to spare. This includes countries with safety nets capable of bailing out individuals who mess up.

Might not be the case in Australia, but it certainly exists.