The more users there are, the less Bitcoin will be controlled by a few people in the market. Of course, at a certain stage of mining, it is not impossible to rivet whether the price stability will become the world currency. You can print as many dollars as you want, but Bitcoin No, I think this is the basis for Bitcoin to become the world's currency.
No, I think that is the reason why the government will strongly oppose Bitcoin being used as an official global currency. Being an alternative is good enough though. Bitcoin since its creation is a global currency ready but majority of the government isn't ready to adopt it even as an alternative currency due to the fact that government cannot control it and can't mint more of it as much as the government wanted.
Definitely, cryptocurrency will weaken the grasp and control of the government over the financial industry if most of the world population adopted Bitcoin.