The thrust of it is that the federal government would withhold funding to municipalities unless they meet certain home-building targets.
Critics worry that this will accelerate suburban sprawl in order to meet quotas. There are some provisions regarding rental housing and transit infrastructure, but with unrealistic time/budgeting constraints.
Even if you take only 10% of Canada’s land area, that still exceeds the land area of 160 other countries in the world, including many with far larger populations such as Pakistan (6x the population of Canada with less than 9% of the area). By the way, Pakistan is a highly mountainous country with more than half of its area covered by uninhabitable mountain ranges and deserts.
You didn’t address my points about investing at all. I think there’s a pretty good case to be made that governments are fighting against the construction of new subdivisions in order to protect the property values of existing single family homes. It’s not about stigma, it’s about the fact that too much of the upper middle class’s wealth is tied up in real estate and the government is terrified of jeopardizing that!