The government's own Housing…

The government's own Housing Affordability Task Force concluded that:

“But a shortage of land isn’t the cause of the problem. Land is available, both inside the existing built-up areas and on undeveloped land outside greenbelts. … Most of the solution must come from densification. Greenbelts and other environmentally sensitive areas must be protected, and farms provide food and food security.” (Housing Affordability Task Force report, p.10)

Does this not mean the the changes in this proposal are unnecessary? What purpose do the changes in this proposal serve if they are not required for housing affordability? Does the government have other research that makes a compelling case that more land is required to increase housing affordability? If so I would like to be provided with those research findings and/or reports.