JUST SOME THOUGHTS AND SPOILERS AHEAD
The whole movie is about time and its consequence on the hollywood industry.
Rick Dalton denotes the past.He had his glory days but he's racing towards the finish line of his career.
Cliff Booth denotes the present just going with the flow.
Sharon denotes the future of hollywood,highly succesful(both family wise and career wise;her husband is director Roman Polanski)
The killing of Sharon Tate on the dawn of August 9th by the Manson family, in real life led to the end of the so-called golden era of Hollywood,after Sharon Tate's death;historians say it gave rise to hippie culture in The USA especially in LA where all the movies were made.....it had a great effect on Hollywood and hence critics say the golden age of Hollywood ended with Sharon's death in 1969....This impacted movies in a way by which talented actors like Rick Dalton never got a chance to portray and display their talent at all...moreover commercialization of hip movies started to intensify giving way to
movies as a mode of making money rather than seeing it as a form of art.
Now,Tarantino being a hardcore lover of movies wouldn't wanna show that tragedy once again.
He's blaming the society with that burn in such a way that we could have saved LA from the hipster revolution, thereby saving Sharon and ultimately cinema but we didn't or couldn't.
Although, If he had managed to pull it off,even present day would have been the golden era.
So,the climax of Rick meeting Sharon and Sharon is still alive shows that Rick has a future and Sharon is still there,that is, there is still a "future" to whatever art form cinema was associated with before 1969.
He rewrote history to make that point.
The end of a beautiful movie about Hollywood opens the gate to a new future of Hollywood rather than a past tragedy.
So,Sharon is the soul of the movie.
U don't have to see the soul,it'll just be around and stick with you.
I really wish I could love someone/something the way Tarantino loves movies
Its just so dreamy and pure