You are all missing the point. If people do not want to trade the money, they will make them non-liquid. If they do, then it they need to have it liquid. Steem power, means there is no liquidity. Paper wallets are a solution but were forbidden by the government where bitfinex operates. The problem is bitfinex is operating in the wrong country.

Two factor authentication is only for you authenticating with bitfinex and not with the blockchain itself. An insider can still steal what ever is liquid.