His face just looks too damn old to be Obito. Look at this shyt:
He looks almost as old as Danzo or Mifune
I don't think its him, it could however be Obito's father. Think about it brehs, Obito's dad probably thought his son was in good hands even though he was a bit of a fukk up he had the son of a legend(kakashi) and the GOAT Jounin at the time(Minato) on his team. He was promised his son wouldn't die but they couldn't keep that promise and he got murked.
After the war when his parents found out, his mother was so heartbroken that she commited that(Obito was their only child) and the shame was almost unbearable for Obito's dad so he too was about to end himself after going on a long walk and entering the same spot where his son died until he ran into Madara. Madara got zetsu to dig up Obito's body and recovered his left eye and Obito's dad started wearing the eye as a sort of keepsake, the only thing he can remember his son by.
He was so mad at the village for letting a war pop off and letting his son get killed that he didn't hesitate to join Madara (Afterall he has nothing to lose now that his son is dead and his wife is dead as well and his village let him down). The reason Tobi wears a mask is out of shame because of the loss of his son, and he has the other eye of the mask covered to pay homage to him.
It can't be Obito because he's just too damn old. According to him, he was old enough to have given Nagato the rinnengan when he was a child and old enough to have met the 4th mizukage. At that time Kakashi would've still been too young, in fact Tobi gave Nagato the rinengan at the
2nd shinobi war but Kakashi and Tobi were still kids by the time the
3rd shinobi war was going on. It might not be Obito's dad, but whoever it is, there's no way its Obito simply because of how old he is.