George was so clear as to how that works. The canon that he created was the Star Wars saga. Right now, episode seven falls within that canon. The spin-off movies, or we may come up with some other way to call those films, they exist within that vast universe that he created.
There is no attempt being made to carry characters (from the standalone films) in and out of the saga episodes. Consequently, from the creative standpoint, it’s a roadmap that George made pretty clear.
I found it interesting that the spin-off films still do not have a genre title the franchise wants to brand them with yet. I wonder if that means the origin tales will be under a specific banner (Star Wars Origins: Boba Fett for instance)?
Kennedy made it very clear she was interested in honoring Lucas’ plans and roadmap for the Star Wars Sagas to come.