Fair enough..It could be inferred since he said everyone would be happy with the IT for starters, secondary, When Obito said he would make Naruto Hokage in the dream world he just meant that Naruto would be Hokage in NARUTO'S dream. Especially since it was also Obito's dream to become Hokage, so why would he make someone else Hokage when he wants to be Hokage...
Those were my reasons to believe that everyone would have different dreams