How do you know they didn't create BTC?
Because btc was created by genius level intellect for the good of the people...that's why.
And who is this anonymous person you speak of? And why are you sure he is for the good of the people?
Whoever Satoshi represents and because of the nature of bitcoin. No corrupt government or bank or agents thereof would present this for the best interests of the people and the best interests of their financial freedom from the corrupt financial industry.