I think the point is, if we tax the rich too much, they have every reason to move away, and not pay any taxes.
Then the guy in the middle has no job, and everyone loses.
For instance, Cabela's the mega outdoor sports chain, recently put a giant superstore literally, on the state line in Idaho. The store is there to service Spokane residents, but they built it in Idaho because they pay less taxes. They still get most of their revenue from Washington, but paying us no taxes.
Big business and the people who own them have plenty of options. What is keeping them from taking thier business with all the taxes, and the jobs, then still selling us their products?
GG wealth redistribution.