What I've always found troubling is the arbitrary, bureaucratic requirement that a person needs three times the income to pay the rent.  That requirement immediately disqualifies most of the people making the median income.

The reality of the situation is that a lower income person has to spend more than a third of their income on rent -- on up to pretty close to their entire income on rent and other fixed costs, like food, transportation, clothing.  They don't need to reserve another third of their income for travel, entertainment, gifts, insurance, retirement savings, fine dining, cigarettes and alcohol, etc.   They have to spend every penny on actual basic needs.  Otherwise, you arbitrarily disqualify huge swaths of the population from even being considered from the housing stock.

In a real world example, a $100 rent increase would then require a person to have a $300 pay increase to cover it -- which of course immediately makes the problem grow worse -- often just by writing it.