UBI can be implemented in a different way. Tax a portion of the profits earned and reserve it specifically for UBI. It is not an allowance either. It is what will keep economy afloat. Else if no one can buy the products/services the rich sell, then their stocks will be worth nothing.

> We cannot claim to live in a democracy while Elon Musk gets to decide whether our allies can use communications or close down entire branches of government.

This can be fixed with laws around lobbying.

> capital controls for the more near-term issue

Capital controls won't solve much because it is a one time exit tax that stakeholders have to pay to move out of the jurisdiction taxing stocks. Those who cannot move will shutdown their companies and invest those proceeds into assets, typically immovable (like land/houses etc), which will drive housing prices up. It has cascading effects that affect the economy in a different way.

This causes displacement of those who cannot afford housing, which will incentivize the rich outside the jurisdiction to buy up assets and then that causes a change in voting structures. The rich can then vote their candidate who will reverse capital controls. Or maybe they won't and keep it that way so they have their own gated society so to speak with no entry for those who cannot afford to be there. You can already see it happening in few places in the World where such controls exist.

> You dont need incentives for the rich. You can just pass laws limiting their options.

You are missing the point. The incentives are for everyone who want to give it a shot at trying to take their idea, implement a vision and then execute on it. Does not mean they will succeed. The tiny percentage who do succeed end up becoming rich. See the number of startups that succeed vs those that failed. You are not disincentivizing the rich by imposing wealth tax. You are disincentivizing the average Joe who wants a shot at making it.