*before Madara shows up*
Obito is a mastermind manipulator, who tricked thousands of people, remained calm and prepared even in setbacks, killed off characters just by simply choking them or snapping their neck and Naruto+Guy+Kakashi+Bee only succeeded in breaking his mask. Such an epic villain must have an epic backstory!
*after Madara and Obito talk*
Obito is being manipulated by Madara, who tricked him into believing he gives a shit about peace, then got scolded for the setbacks the plan underwent, is now ordered to fight Kakashi and Guy who, according to NB, are totally gonna kill him. Who cares about his backstory, he's not even the main villain.
Blame Madara xD
In seriousness now, I think it depends on how Kishi is going to develop Obito. In the back of my mind, this is still the same guy who had a huge number of epic lines and scenes. The face design is also extremely well done, so the revelation wasn't really a disappointment.