Bitcoin is not distinctly associated with a social media / blogging platform the way that steem is. The value of steem, in my opinion, is inextricably tied to the perception of this platform. Very few exchanges offer it for trading/investing. Accordingly, the daily trading liquidity is minuscule compared to the Top 10 cryptos. Unless it is marketed with a focus more on the benefits of the steem blockchain itself. Which may in fact be happening with the push towards SMTs.