You might recall that theory of how E.T. is actually a Jedi or a Sith Lord. If not, it's very simple, and pretty easy to follow, as there isn't much to it.
E.T. Has Cousins...Or Very Distant Relatives In The Galactic Senate...
E.T. Recognizes Yoda...Or A Creature Who Looks Like Yoda...
And E.T. Has Force-like Abilities...
As you can see from the above clip, and all throughout the film, E.T. wants to help heal/fix things, and he uses his "abilities" to revive and also...fly! But you see, we know from Star Wars that Jedi's don't use The Force for evil, but help protect what is good, and that the Sith/Dark Side are the only ones that practice the evil dark arts of The Force, like reviving the dead.
That brings up, many questions to how E.T. can then use both the Light and Dark Side abilities of The Force. But the only one that really sticks out, is that The Force is a dieing thing, and only a select few can even use it.
If we look back, E.T. didn't recognize that thing as Yoda, but as a fellow alien creature who's at home, or he's telling it to go home.
But what if we're looking at this whole theory the wrong way; and we need to look deeper. Like, what if E.T. and his race of aliens are the last race to even have The Force? And how does George Lucas remember these things?
Well, if George Lucas had these "visions," which he made into films, and continues to make, then that would mean that everyone from the past, Rey, Luke, Leia, etc. are heading to a time when The Force is a dieing breed, and George so happens to be one who has it.
That being said, the whole,"a long time ago in a galaxy far far away," is indeed the past of Elliot and E.T.'s universe. All the events of Star Wars have already happened, and The Force is dying off.