So as a secure bank account, Steemit could find a niche because I don't know any bank account, stocks or bonds which pay 10% yield annually.

Maybe you have the answer right there. Steem and Steemit have what? 4-6 months? Do you understand how the SBD dollar peg works? Did you see some Steem graphs lately? Do you know what's the current traders sentiment towards or opinion about Steem? Do you consider an experimental platform with only some months of testing and still in beta, that was already hacked, a proven system already? You are literally telling people their money is safer here than buying a bonds, funds, stocks or even or putting it in a bank , think about that for a second.

I'm not trying to spread fud, come on...this is just non-sense sorry.

The answer to these questions by the way is yes, a well managed portfolio will give you around 10% and possible more with much less risk.