I wrote a post recently talking about the nature of what needs to and what doesn't need to be tagged, and that kinda ties all this droning I've written below. Magic... technology... what constitutes these terms is defined by the world in question, which makes them poor at their base level for tags. If you are looking for high science material, you don't want to run into a question asking about magic catapults. And that's where I see that people would actually want to be looking at divides. My main point here? From a categorical perspective, "Magic versus technology" is a poor divide so instead look at more useful divides to answerers like whether the nature of the technology is "powered by etheric means" or if it's powered by the same mechanical logic we observe in our own world. Tag and label things on this site not based on logical categories but based on what you, as a community, will actually use.
The raws of terminology, that can be handled by the question body. And in fact it should - a question that wants to talk about magic or technology within a world should really provide the nature of such systems in order to be properly understood. Even if it is referential to existing works, an asker still needs to supply the information necessary for answerers to genuinely assist them.
The rest of this answer is kinda ranty in general about the concepts of "magic" and "technology" but it's how the above point all comes up from, so it may be a nice read for some folks so I'll include it anyway.
Think about how this site is running. We have people asking about things like biological diversity and geological structure and all these things, trying to figure how things would work in a theoretical world based on how things work in our own world. That's great and it's a fundamental means to establish something that is comprehensible to the player or reader of your world you create. It just kinda fails when you look at a divide like "magic versus technology" because magic versus technology is not a perceived divide that exists in our reality. By consequence, the nature of what is defines magic or technology depends on the perspective of the world being built.
Technology takes its roots in how we had progression in this world - we had this distinct medieval age of stone castles and swords and candlelight, then we had this distinct period of innovation with inventions such as the electric light and the combustion engine, and then computers happened and so we have all these distinct classes of technology we can group. They're logical and there's nothing wrong with it, but the root comes that all of this only happens because that's how it happens in this world. Ours is a reality perspective which does not contain comprehended magic to the layperson. Our technology is derived entirely without the influence of whatever mystical existences may be hidden from our perception. This leads to my main point that as a consequence of how we know of our own world, there is no solid or universal concept of magic in the realm of worldbuilding.
Let's take some examples of things.
- A world locked in medieval stasis where sword and sorcery are wielded alongside each other. I'm not going to elaborate more because this is a very common and easily understood example.
- A world similar to the 1800s, but where there are "wizards", who can cast "spells" by using a gigantic rifle-cannon and loading it with special bullets created from materials such as powdered dragon bones. The nature of the material determines the power, and settings on the gun determine the end result of firing the bullet by applying new kinds of physics to it - suddenly the bullet cuts through space itself, or suddenly it produces flames, or suddenly it provides a mental map of the surroundings. It's a very methodical process that is rather well understood, though only some folks are capable of utilizing it.
- A world set thousands of years past ours, where there are machines which are powered not by electrical current, but by the induction of "dynamo blood" found only in the hearts of half the world's population, due to a particular hereditary origin line. Make coffee in a coffee machine by sacrificing your own life force, which replenishes overnight as you sleep, and thus by extension save yourself thousands of dollars on the electrical bill. Each year, new kinds of machines that take advantage of dynamo blood are created in order to reduce the strain done to the planet's resources.
- A world not unlike our own, but every once in a while a "mutant" is born. This mutant has special powers like the ability to teleport, to regenerate from any wound, to control ice or fire. It apparently finds its roots in strange genetic mutations, and the concept as a whole isn't wholly understood - it is acknowledged that it exists and that it happens.
I could make more examples but I hope these illustrate my point clear enough. How many of these would you say are magical in nature? And what makes you call them magical in nature? You might find yourself sitting and thinking, and if you had to sit and think any bit that's my point here.
Because of the lack of universally acknowledged "magic" in our own world, the identity of what is classified as "magic" in a created world must come from the perspective of that world. We lack any analogues in our own world to make for it, unlike what we can do with technology. But that comes to another fault point - technology and its advancement are defined by the resources available to a culture, and that culture's ability to understand, explore, and manipulate the given resource. That fine divide of the knightly past, the electric modernity, the robotic future - that all is derived from the perspective of our own reality. This causes the root existence of technology - technology as the collection and development of tools and machinery of any sort of make, to be confused with instead the idea of "technology derivative of highly-advanced-science". It's taken me far too long to reach this point but it is the other half of my important point that I started off with. Since we lack magic as a counterpoint to technology, we default to the idea that "technology" refers to what we have. In a proper world setting, though, if they had different resources due to the presence of some supernatural or mystical force, technology would be affected based on the nature of the resource.
Does that make it scientific or magical, though? That is how we get back to the dependence on the perspective of the world, and by extension why it is a problem to try and make that kind of sweeping categorization on this site. As a site, we cater to this world, we cater to the perspective of the worldbuilders themselves. Especially with a system like tags, there has to be a shared meaning that applies or else there come misconceptions and misuse and the categorization falls apart. Context is important for these things - "What happens if we introduce magic into X technology" is at raw point pretty easily recognized as terrible and it all comes from the root fact that magic lacks a universal definition to us, and technology's definition comes scoped from the world in question.