You say no need, I say massive need if there’s to have good storywriting in the movie or any logical story progression. And yeah they might include it in the next film…how is that any sort of defence? I think more likely Rian Johnson just sh*t all over most the characters and wanted to throw in his own Shamalayan twist at the sacrifice of good story telling.
I’m basing the review on the movie, not post released Force Awakens Disney fan book that tells you nothing other than he’s force sensitive, and literally has nothing to do with the movie that was released.
This is what Rian Johnson said about Snoke:
“I don’t want to imply that that’s not interesting, or that’s not cool, or it doesn’t matter. I think, who knows, they might address it in Episode 9. They might address it elsewhere.”
So good on him, he doesn’t really care, it’s not his problem anymore.