The series has never been science fiction.
I think the difference is that in sci fi stories they always have a scientific explanation for things. Star Trek is a good example of this. Tricorders, shields, phasers, warp drive, impulse drive, and replicators all have in-universe scientific explanations. They might be made up, but there is no element of magic in any of it.
Star Wars, on the other hand, doesn’t really get into those things. Yes, there are technical manuals, but we don’t see engineers on the Death Star reversing polarity. And nobody liked it when they tried to have midichlorians be a scientific explanation for The Force.
So I would agree with Mr. Hodgman that Star Wars is, in fact, a fantasy. It’s a space fantasy, but it definitely lacks the “science” part of “science fiction.”
in sci fi stories they always have a scientific explanation for things
I think there are two issues with this: it’s not a requirement that sci-fi explain things; and it’s not clear what would qualify an explanation as “scientific”.
I would say, rather, that the implicit set of laws governing a sci-fi world are a superset of those currently understood to govern ours, while in a fantasy world the governing laws contradict those governing ours.
