And the difference between science fiction and fantasy can be summed up by Arthur C. Clarke himself. Any technology sufficiently advanced will appear a magic. Soft science fiction leans toward assuming we will find those advances and tries to not explain them very clearly (often not explaining typical tropes at all). When the tech is low and you still have magic, that is when you have fantasy. That is the line between science fiction and fantasy. If you provide tech to do the things that seem magic or provide even a quasi scientific explanation for it, it is science fiction. If there is some mystical source of the power - some deity usually - then you have fantasy.
Even by your arbitrary definition, Star Wars is still fantasy. The only time in the films provide a “quasi scientific explanation” for the force is TPM, and it’s no surprise that that’s one of the things people hate the most about that film.
You can split hairs any way you like, but the fact of the matter is simple. Star Wars does not care about how tech works. It never has. How does a lightsaber work? Oh, a crystal of course. A fucking magic crystal. The laws of space physics are completely irrelevant. It’s not just ‘sound in space,’ it’s how the ships move, it’s how an asteroid field is dangerous to traverse when in reality it never would be, it’s how long it takes to get from place to place, and yes, it’s whether or not you can see a beam shoot across the galaxy. When a new piece of tech arrives in the Star Wars universe, checking to see if it fits into how things work in reality is the exact wrong way to do it. Whether you think it’s fantasy or not (it is), you cannot disagree that is is a significantly fantastical world, where tech and physics follow a fundamentally fantastical set of rules.
Ben called it an energy field. Try finding that term in fantasy. That is an SF quasi scientific description.
Most space operas don’t care how things work. Most things just work. Read some of the classic space operas. Does Isaac Asimov ever explain how a force field belt can have an atomic power unit the size of an almond? No. Does he explain how the force field works? How it covers the body while not extending to other things? No. That is space opera - a long standing and respected genre of science fiction, not fantasy. You are looking at this through the eyes of hard fantasy. For many of those writers/readers/fans, most things that are called science fiction are fantasy, but theirs is the minority opinion. Fantasy doesn’t claim it, science fiction does. And in truth, both are part of the larger speculative fiction genre and share many of the same awards. Both came from the old romance adventures, such as Ivanhoe. Science fiction just introduced science to the mix and was pioneered by many as far back as Cyrano de Bergerac, then Mary Shelly, and most famously Jules Verne - considered the father of modern science fiction. Fantasy was born out of the Arthurian legends and then exploded after The Hobbit. But the big difference is science and technology vs. magic and myth. Star Wars falls on the science and technology side and is not claimed by the fantasy side at all. Where is the magic? If you say the Force and the Jedi, you aren’t up on what cuts it as magic. As early as 1977, Lucas had Ben explain it away. Yoda further explained it away. As simple as that may see, that is more than Tolkien ever did. Magic needs no source or if it does, it has a source that science can’t explain. But the distinction between science fiction and fantasy is magic vs. science and there is way too much science in Star Wars for it to be fantasy. It isn’t hard fantasy by any stretch, but it is soft fantasy - specifically space opera.
The real point is that science fantasy isn’t a modern genre term. It is not in use at all. It is championed by some hard science fiction people, but most of the science fiction publishers and writers put out soft science fiction that is very similar to Star Wars. Some people have called out Star Trek as science fiction while saying Star Wars is science fantasy. Sorry, but they are the same. While the stories they tell have some differences, both rely on the same tropes. Sound in space, telepathy, telekinesis, instantaneous intergalactic communication, faster than light travel, artificial gravity. energy weapons with visible beams, people shooting lightning out of their hands, people controlling other people, robots, questionable science (at times Star Trek has been better, but when they aren’t they are worse than Star Wars). In fact, Star Trek features beings who could beat any Jedi or Sith with little effort. Some of the beings featured on the original and next gen were so powerful they really couldn’t be beat. Not by force anyway. So there is no more magic in Star Wars than there is in Star Trek. Are they both science fantasy? Well, the proper genre term is space opera. Has been for 70 years. (Space Opera - a novel, movie, or television program set in outer space, typically of a simplistic and melodramatic nature.)