Well in an attempt to answer your question without much delay, I'd say Steemit cannot possibly replace Facebook not now and not anytime soon.

Facebook as a social media revolutionalized the history of social communication. It created a platform through which globalization of information takes place and led to the miniaturization of the media.

Facebook heralded the concept of the Global Village and made the world a smaller place by letting people communicate across national boundaries freely without any hindrance. This feat alone achieved by Facebook is one of the milestones that steemit cannot and have not met.

Facebook as a social media keeps updating it's platform with a lot of additional features but it does not give the opportunity to earn on it's platform unlike steemit.

Steemit on the other hand was built on the block chain like every other crypto currency and gives the opportunity to earn while we post on the blog but it's still way behind the Facebook platform as steemit does not get as much traffic as the Facebook platform and might not get as much as that in the nearest future.

Don't get me wrong, steemit is a very good platform for people to Post and earn but its still has a lot to do if it plans on replace the much announced Facebook all over the world.

Every average citizen of any country have a Facebook account but not every average citizen of every country have heard of steemit not to talk of having a steemit account.

But I'll like to applaud steemit for the continuous growth and upgrade and believe that if they continue yo step up their game, they would some day rub shoulders with the Facebook platform