Question: Who is the main owner of Bitcoin community/exchange?
No one owns the Bitcoin Community.
It’s not even the well-known Satoshi Nakamoto, US government or some developers.
The Crypto-currency market is powered by its users and the transactions are also recorded online by its users.
The market value will be decided by the balance of supply and demand and no one know if the Bitcoin is a bubble or will be a stable currency in the future yet.
It is also true that on one can force a change in the Bitcoin protocol, as Bitcoin can only work correctly with a complete consensus among all users.