I have to ask, did you say the thing at the time the supposed exodus was getting lots of media coverage? I expressed skepticism about it at the time, although I did not pay it too much attention because I don't live int he UK. But any skepticism about such a prediction always incurs a bunch of people insisting I don't understand economics and explanation of how freely the wealthy can flee a high tax jurisdiction.

I notice you don't identify any particular investigative shortcomings or fallacies in the report; you just think it's absurd to even consider the viewpoint of an organization that argues the wealthy are undertaxed.

The original report this article responds to was out put by a company that sells golden passports, and their study involved trawling linkedin. If there are concerns around methodology and bias, then you are absolutely right we should start there