That would only encourage billionaires to nope off into space fantasy land (and of course they would still maintain power over governments). As it is right now, billionaires being on the same planet as normal people is at least incentivizing them to keep the planet in somewhat hospitable conditions.
As it is now, the best course of action would be to depose billionaires more quickly than they can escape off-planet. And to do it in a public and spectacular way to put fear into the billionaires










I mean… If we treated the sun to be just another star (ie, if the astronomers got their way), the planets would probably be called Sol b, Sol c, Sol d, Sol e, Sol f, Sol g, Sol h, and Sol i.
Sol a would be reserved for the sun, of course.