This has become a really popular idea that the majority of readers seem to agree with, I don't see it though. However, I will preface this by saying last time I disagreed with the majority (the mysterious foot being Kabuto) I was proven dead wrong. But, well, here it goes.
I hypothesize that Kaguya was too powerful for Hagaromo to take out by himself, so he gave both Naruto and Sasuke Riddokou power ups to take out Kaguya for him. Now that Kaguya's out of the way and Naruto and Sasuke apparently no longer have their Riddokou power ups, theres nothing from stopping Hagoromo.
I'm gonna focus on this, because I disagree with all of it. You say, "too powerful to take out by himself", but taking Kaguya out is something he has already done. Any so called "evil plans" Hagoromo has could have been accomplished when he first sealed the Juubi, when there was literally nothing stopping him. Think about it, after he sealed the Juubi initially, he was maybe the most powerful thing to ever exist, that would have been the time to do something. But, what does he do? He has two sons, teaches them Ninshu, learns through his younger son that "cooperation" is the key to true power and because of this he proceeds to split his own strength into 9 beasts believing that they will restore peace and balance. On top of ALL of this, he explains to the Bijuu (in private I may add) that some day they will learn what "true" power is (the ability to help each other) when they meet the boy of prophecy, a.k.a Naruto. On TOP TOP of all that, let's not forget where this prophecy comes from, the Toads. Who's association with Ninja's has only been good.
The only evidence people have for Hagoromo's evil intentions are the faces he makes, which is silly. Again, this could blow up in my (and people who share the same opinion) face, but the evidence against Hagoromo being evil far outweighs the contrary (which let's be honest, is nothing more than a hunch some people have).
What people should be focused on is the Giant Rabbit that spit Madara out, because it most certainly was not Kaguya.
