Maybe he thought people would happily give up their steem for some new tron token in which the future steemit would run on? (but it would only make sense if the majority users are thinking "steemit = steem")
Basically its an investment for him to increase tron users?
After seeing the livestream i feel like justin is flexible enough to change his original plan and let steem and tron run separately.
Maybe now steemit would get you steem and tron? Who knows.
Id be ok with earning both on steemit :D
now we know justin is back to his "original plan"
we're not that lucky lol