What kind of housing someone can afford is a political question. Our current answer to it is that this should be resolved through market mechanisms, which creates high prices alongside scarcity
Transitioning from land prices to land rental values - i.e. gradually moving toward a 100% land value tax - would address both high prices and scarcity by taxing land consumption - and, accordingly, encouraging urban density in order to amortize that tax, thus alleviating scarcity and reducing residential expenses. Same market at play (a land value tax definitionally taxes the market value of land); vastly improved outcome.
People act like renting is some sort of evil forced upon people, but don't realize there is a big market for renting. People don't always want to own their own housing.