No, we can’t address affordability by building lots more apartments

Sure did. Vancouver became the world's least affordable housing market. Not a great outcome if affordability is your objective. Don't be like Vancouver.

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Yes, townhouses are a halfway point in build costs. Suburban renewal precincts with townhouses or low set apartments are a more affordable answer, but even this is a challenge given construction economics.

No, outer suburban detached housing will not result in more people trying to get to the inner city for work. These buyers typically don't work in the inner city. Inner city workers are typically higher paid. In New Farm for example, one in five households earns over $4000 a week. Inner city markets are high income markets with high-cost real estate. These people typically don't work in the suburbs at a hospital or in retail or in education.