The maximum it can increase the supply of housing is much less than 100%.
(Also, I realize now that’s not quite right because of the way percentages work: e.g. if the investor owned all the houses and left them vacant, then eliminating the investor and putting them back on the market would technically increase the supply ∞%. The more correct way would be to say it could increase back to 100% of what it was originally.)
The point is, the amount of housing that could be made available has an upper bound of the amount that the investors are keeping vacant, which is only some fraction of the total that currently exists. Meanwhile, allowing higher density could allow orders of magnitude more housing to be created.
The maximum it can increase the supply of housing is much less than 100%.
(Also, I realize now that’s not quite right because of the way percentages work: e.g. if the investor owned all the houses and left them vacant, then eliminating the investor and putting them back on the market would technically increase the supply ∞%. The more correct way would be to say it could increase back to 100% of what it was originally.)
The point is, the amount of housing that could be made available has an upper bound of the amount that the investors are keeping vacant, which is only some fraction of the total that currently exists. Meanwhile, allowing higher density could allow orders of magnitude more housing to be created.