If they take salary, they pay tax. If they buy property and then take loans against it, no taxes. Add in money laundering from overseas accounts (many held by Americans) and the market is no longer connected to occupancy.
One would be shocked at how many owners of high-end properties have never visited those properties.
a member of a toilet paper dynasty bought property all around an up and coming city and then ran them empty for the tax write off he needed thus turning a former economically vibrant area into a ghost town