Then there should be a centralized power whose only power is to enforce the decentralization of power. Basically people should get paid if they can legally prove that someone has too much power in a trial. There should be a felony 'Overaccumulation of power' which may carry a temporary/conditional jail sentence and a special court made up of a large random jury who vote on each case.

With enough signatures, anyone can be brought to trial. The jury is asked to vote to determine if a person or entity is too powerful or too well known. Also, there should be a wealth limit so if wealth is above a certain high limit (like $100 million; set by a special panel), they are offered to either donate everything above the limit to a UBI fund or they go to a special jail until the amount falls below the limit (evaluated by a special, large, randomly-selected parole board).

I think such system would out-compete centralized systems which do not have such limits as it would be more efficient economically.