
Why not? I think it should be taken seriously enough to be modeled when discussing tax policies. You need to tax high enough that you can maximize revenue, but not so high that it becomes significantly cheaper for the wealthy to move their money to shell corps in the Cayman Islands, causing you to spend a lot on tracking it down
High earners have little to no mobility, most of their wealth is tied up in businesses, real estate, financial networks and the US Stock exchange, the idea that this can all be packed into a bag and moved to the “Cayman Islands” is laughable. Besides, we can look at Europe (specifically the Nordic countries) and see that there is no mass elite exodus is higher taxation is paired with infrastructure and market access. Simply put, we’re taking away their ability to have their cake and eat it too.