Like
the Guardian? In fairness this isn't a new phenomenon.
The rich may not want to move to a tax haven but they don't need to leave for a tax haven as such. They can just go somewhere where the tax regime suits them better. Or where there isn't a wealth tax. America for example. Probably much of Europe.
It's happened before. You can easily look up all the film stars and rock stars who left the UK in the 60s and 70s because of high taxes (they weren't the only ones but their profiles are higher so easier to find). You can listen to Taxman by the Beatles. And it's much easier to move around the world now than it was back then. As I mentioned before, Francois Hollande introduced a "supertax" on the wealthy in France in the 2010s.
Loads of the rich left so he was forced to abandon it.