I believe you're serious!

George Lucas intended Star Wars as SF. He was inspired to make them by classic SF, particularly E.E. "Doc" Smith who more or less created the "space opera" genre.

There is a single card on the screen that says 'A long time ago". And so? Plenty of SF is set in the past. (My favorite is Anderson's "The High Crusade".) Plenty of SF involves psychic powers.

When he released it, SF fans (including myself) went berserk.

The concerns of SF and fantasy are totally different and this is SF.

If you recall, the whole plot of the first released film is this: "A boy learns a technological weapon, and then flies in a spaceship with robots to destroy a huge new technological space station by flying in smaller spaceships and taking advantage of a technological error in the technical design of the technological space station."

The trope of "a single person sacrificing themselves so the group can escape or overcome an overwhelming force" happens in almost every action movie, and has nothing to do with whether something is SF, fantasy, a comic book, or a spy thriller.

And movies which are about "growing up" are even more common.

Neither self-sacrifice or having character arcs makes a work "fantasy".

Finally, I would add that all reference sources, from Wikipedia to the Encyclopedia, class Star Wars as "space opera" which is a genre of SF; that every single "top SF movies list" I could find includes Star Wars; and that not one "top fantasy movies" list that I could find does.

So you're clearly out of touch with nearly everyone else.

Star Wars is a series of movies about outer space, space travel, space battles, psychic powers, aliens, robots, blasters, lasers. There is advanced technology in each and every shot. It is science fiction.