Too Long; Didn't Read
Bitcoin is a decentralized medium of exchange, not a monopoly, it's a direct alternative to the government's monopoly on money. Bitcoin is the only real challenge that the modern financial system had to face in terms of competition was when the blockchain first became available. Governments from all over the world were trying to prevent its expansion as early as 2014-15. But what if the one who's tasked to control monopolies, governs the largest monopoly of them all? What about currencies, or money in general? Who prevents monopolies there?