https://comptroller.nyc.gov/reports/the-pied-a-terre-tax-and...

> It is unclear how DOF will treat properties owned by LLCs and trusts. In general, these owners are not considered residents. However, this does not mean that the properties are not used as primary residences. For instance, based on publicly available information, Mayor Bloomberg established his primary residence in two adjacent buildings on the Upper East Side, one owned by an LLC, and the other a cooperative apartment corporation. It may be possible for some LLC owners to rent to themselves and avoid the tax.

The tax is based on residency, not ownership. If nobody lives there as their primary residence, it's subject to the tax.

That's a great point. I'm guessing the politicians knew the rich would find a work around, but they're obligated to go through the outward motions so they can claim to keep their promises.