I also saw Blade Runner in its original theatrical release, and it's still the version I prefer. In this case I think the studio heads did Scott a backhand favor by ending the film as they did.
Spoilers:
If, as depicted in the original release, Deckard is human and Rachael is a replicant, then the movie is a true love story. The message of a true love story is that the Other is as deserving of love and dignity as I am. It's the message of Romeo and Juliet, Frankenstein and To Kill a Mockingbird, to name three offhand.
Whether your allotted lifespan is four years or threescore and ten, if you understand that you don't know how much time you really have, then you are entitled to the full measure of decent regard and respect the melancholy of that understanding earns. Batty bought that respect for Deckard and Rachael's sake. Thus the original ending is moving, and completes the film's overall themes.
If Deckard is also a replicant, as subsequent versions try to establish more and more explicitly, then of course he's going to want to be with Rachael. It's a no-brainer, it's no sacrifice, and there's no moral revolution of the characters. In which case I don't really know what the movie is supposed to be about. Boy robot meets girl robot, boy robot loses girl robot, boy robot gets girl robot? Boring. Definitionally cliché.
I suppose the realization of it is supposed to be some kind of shocking twist, but to me it simply empties the film of meaning.