People don't hoard houses, they hoard land. Taxing houses results in fewer houses, but taxing land doesn't result in less land. Check out https://astralcodexten.substack.com/p/your-book-review-progr...
I like the idea of a different incentive structure: no taxes on the sale of a newly built housing, high property taxes on houses with an exemption for primary residence, and leave the existing property tax structure for business and fallow properties alone. This way you encourage new housing being built, encourage ownership and not renting out housing as a business or sitting on houses to flip them.