You: "row upon row of vacant luxury properties represent significant capital inflow!"

Real world: vacant luxury houses can cause blight and other problems just as much as low-income housing.

Also, the value of the vacant property does not decrease because it is occupied. Unless your claim is that the local burden of people existing in a community is larger than the combination of their property and other contributions.

So an occupied property represents significant capital inflows AND enhances economic well-being on a per capita basis, AND does so moreso than the vacant, because there's the capital inflow AND the local spending.

Otherwise you end up with the absurdist trope of talking about public budgets as "homes and communities are worth more if no-one lives in them".

"Assume a spherical cow..." "Assume a row of oceanfront villas that have roads and sewage and utilities that require less maintenance because they're all vacant."

Phrasing it, as you repeatedly do, as "envy-driven" and "anti-free market" and libertarian ideology is sophistry. "You just don't get economics" - no, people understand that housing isn't a purely economic construct.