The root cause for the low affordability seems to be that most people don't want to sell a house purchased at 3% interest and have to pay for a new one at 6%. That and zoning restrictions too contribute for the lack of supply.
In my area the zoning is ludicrous. Need to walk 4 blocks to visit my corner store. Tall skinny townhomes that nobody wants and go unsold for months are the only allowed high density option - with no stacked flats.
There was a huge affordability problem 4 years ago when the rates were 3% too, so that’s clearly not the “root cause”. In fact, at the time HN was filled with people blaming the “free money” 3% rates for the lack of affordability…