I can rephrase it: why do you think it impossible for vastly resourceful entities to acquire so much power they can control the decentralized system - in a softer way, probably but still.

Imagine a world tmr where bitcoin is everywhere. You ll have mining conglomerates in the cheapest electricity providers working as cartels to help each other and protect their interests (so can envision centralizing a blacklist of addresses they dislike, coordination on software version etc), de facto cartels of whales (like todays "billionaires" people describe as a collaborative force), and large lenders who concentrate capital and therefore still can buy out whatever they want (today called banks).

How do you think the blockchain solve any of that?