People very rarely actually leave countries over tax policies. Countries pretend ignorance because of who’s benefiting, but unless they renounce citizenship moving money off shore is effectively symbolic.

Loopholes for example aren’t some inherent element of tax codes their built and maintained for the express purpose of being used.

Quite a few wealthy people do. Especially Canadians and non-americans who can.

Why wouldn't person move outside of tax jurusdiction if it afford saving few extra $MM's and possibility to discover more beautiful, friendly countries?

Of course US Citizenship essentially became IRS trap and renouncing it became very difficult thing to do for americans

Of Canadians top 10 wealthiest, 8 live in Canada, 2 are living in the US. That’s hardly an exodus to low tax countries.

So sure, examples exist they simply don’t add up to a meaningful percentage. As to why they stay, making say 10% more money just isn’t worth much hassle to the rich. They have money what they want is all the things a well functioning society gives them.