Facebook could do something similar. They have the money and team to develop it. But no one is asking them to do it because their millions of members are happy to be able to do whatever they do there, without getting anything back from Facebook other than the service of the platform. Everyone is already on there so Facebook doesn't need to do anything to attract new users.

But if Steemit gets big, and people start leaving Facebook, they might make changes. But it might be too late. Similar to what happened with MySpace. Once everyone decides to move on, the old platform collapses. Well that's one possibility anyway! I really don't know what will happen but I'll be here to see whatever does happen!