Most places that have actual magic seem to have a given set of natural laws as well, it's just that some inhabitants can adjust some of these natural laws. Removing localized gravity, creating energy from nothing / converting magic into energy, making objects become without mass or be not solid. There is some structure and set of rules on top of some base though. So perhaps it would be more correct then to say that magicians are capable of altering nature or nullifying physical laws in some ways for some period of time. That where magic exists, 'the laws of physics' aren't always 100% universal. Be that magic alone, tech and magic mixed, tech that works like magic, etc. Even still, places with magic have limitations. Not anyone can do anything at any time in any way. Either because the person casting doesn't know how or isn't powerful enough to, or because such things are even beyond the powers of magic, or because some things take too much magic to carry out. Sometimes there are just some things someone sane doesn't do, like destroying the star the planet they're on is rotating around. Not unless their magic is capable of and strong enough to substitute for all the forces that keep things in orbit in ways capable of supporting life. Or they've got a spell to provide long-term protection from deep space, if they even had some reason to do such things. Unless it was trivial for them and unimportant to them or others... In that case, such a person might very well be indistinguishable from a god. Which goes back to the other subject.
Fort: "a performance that may some day be considered understandable, but that, in these primitive times, so transcends what is said to be the known that it is what I mean by magic." Brackett: "Witchcraft to the ignorant, … simple science to the learned" Ambrose: "Any technology, no matter how primitive, is magic to those who don't understand it."
Yes, the notion is that if you didn't know anything at all about anything technological (and were not genre savvy and were not capable of advanced thinking) science that could revitalize and supercharge old spacecraft or light one on fire from a flaming forcefield might seem like pure magic to you. As would be the notion of spaceships and forcefields. Although that isn't necessarily a fully convincing concept either. Algebra dates back to at least the Babylonians circa 2000 BC, would modern quadratic equations seem all that odd potentially. Somebody from 100 BC who was familiar with Antikythera mechanisms that saw somebody today using a voice-communication-enabled pocket supercomputer might well be able to extrapolate. People were imagining somewhat practical ways to get to the moon long before anyone actually did. (Presenting things like this to far earlier versions of humans (such as Au.africanus) is really another matter. If we showed up 3.5 million years ago, would the brain of that time even be able to recognize we were the same type of animal, much less be able to conceptualize either technology or magic? Would lighting a cigarette or turning on a television make us seem like gods, just cause them to run away in terror from a horrible monster, make them try and kill us for food, or would we just notice the spaceships seeding the planet with DNA and get back in our time machine before we even began. )
Beyond that sort of endless discussion, it's not entirely convincing that this entire 'did she call herself a witch, did she claim to be a witch' rises to these sorts of discussions when it comes to either Alice Grove the person or the location. Yes, to a given observer, they may not be able to tell the difference between advanced tech and magic. Is that the case? Seems the real question is more like if what Alice does appears to be like magic to these people.
Why do the folks in the town call her a witch? Because she does witchy things, even if that's just falling dozens of feet, hitting the ground, and being fully unharmed, or without effort beating up the toughest guy in town. Does that fit, maybe not very witchy at all. Why does she sometimes use that term. It could work to explain her advanced status comparatively, her attitude towards them and things in general. Perhaps even describe to others how she's thought of by the locals. However, the term has been used mostly in flippant, neutral, wry, mocking, sarcastic, ironic, hyperbolic, joking, dismissive ways though. Not seemingly as an claim by anyone she is magical or can perform magic. Which to large extent also rather seems to match how the townspeople use the term, doesn't it? They don't really seem all that under the impression she's magical either. Powerful, not to be trifled with, in charge, indestructible, etc; but not an actual witch or with witch-like power. Nobody appears to believe she weighs as much as a duck.