Where I live in France there was a big relaxation in building permits in the 50s to 70s, and we are dealing with these projects badly designed (because of the lack of oversight) today. Neighborhoods that are urban hell, disfigured city centers with giant hotels 5 times higher than other buildings, etc.
With better planning the same capacity could have been added but with way better quality of life.
> same capacity could have been added
That’s not at all likely.
What you need is to require new construction to have a certain density along with building standards (sunlight, insulation, etc.).
Just deregulating exposes the land to the whim of the developer’s good will — trusting them not to get the most bang for the buck out of building a slum, which is a fickle guarantee.
If there’s no short term profitability, public sector needs to step in. Housing is infrastructure, it’s crucial to the land’s growth.