It’s not, it’s a massive distraction that makes people feel like they’re doing righteous class warfare, while barely making a dent on climate damage.

I think the reason it's discussed is "if I cannot destroy the planet in your country, I'll do that in another country (which won't change anything for the planet) where I'll go invest my money too (which means less money for your country)". And politians seem to buy on the threat, either because they truly believe it, or because they don't want to piss of the rich guys so they can get an overpaid job in one of their companies after their political career.

Because it creates an easy scapegoat for our problems. It's much easier to point to the behaviors of a very tiny group of individuals and lay all the blame on the them than it is to grapple with the real truth of climate change: that our modern society is unsustainable. Barring some grand technological revolution, reversing climate change means bringing us all back to a pre-modern society. And that really sucks.