Seems like this thread has branched into a couple of threads.
Definitions of Magic: Aren't debates over definition a bit pointless? If we stipulate that the definition of magic is any technology or science which most people can't understand or reproduce, then that word "magic" is useful for conversations about that. If we stipulate that the definition of magic is manipulations of the universe which defy the laws of the universe, or at least defy those laws which are demonstrated scientifically to exist, then that just gives us a different word "magic" for a different conversation. Both conversations are valuable, and both styles produce interesting, thought-provoking fiction and discussion, so neither definition is better than or preferable to the other; they're just different words. Different concepts, maybe related but significantly distinct from one another. If a word is a symbol for a concept, then we're using the same symbol to represent vaguely-related but separate conversations. Maybe it's like "love." They say the Ancient Greeks had a bunch of different words for "love," and we've lost that nuance, but maybe we haven't. Maybe people just get a little lazy about using precise labels for what they mean. Or, maybe, in this case, precise labels don't exist yet in English, and we need to invent words or codified label phrases (or borrow a few loan words from Ancient Greek or Chinese or Sumerian) to identify what we're actually talking about.
The actual effect of magic, and superpowers, in the world: There's a couple of nice sub-threads in this one going on...
Power corrupts: I see two sides of this debate in the thread above, and I think both have merit. (First, a definition: "power" here we seem to be using to mean "the ability to impose one's will on other people, regardless of their will, such that they must obey or suffer.") Side A says that power corrupts. If you give any human being power, no matter how moral he was, he will become less moral and more abusive. Side B says that the primary corrupting influence of power is that it attracts immoral, abusive people who are prone to use power corruptly. The latter is definitely true and self-evident throughout history. The former I think rests on a grain of truth: It's not that power corrupts, but that no man is perfect. All human beings are corrupt, and therefore not capable of wielding power over other human beings justly. Any person who holds power will sooner or later impose his inner evils on the people around him, and if he does that without consequence, he will keep doing, and will escalate, because a human being is not strong enough to regulate himself. The two Sides above both seem to imply the same conclusion, though: the only person whom you should ever promote to a seat of power is a person who has the expressed and demonstrated agenda of reducing the power of that seat or elevating the power of all other seats to match it. Only people who don't believe in kingship should be made king, and then only long enough to destroy kingship.
Exclusivity: A founding premise of almost all fantasy fiction about magic (or superheroes) is that of exclusivity. Only a small, select few are gifted with these gifts. But while that always seems to be a part of magic/super fiction, there's nothing about magic/super concepts that necessitates it. It's like... just because every beef you've ever eaten was seasoned with thyme doesn't mean that thyme is a part of beef. The exclusivity part comes from the human nature of the writers, not from any fundamental component or necessity of magic theory. Reality is very different. In reality, traits are either heritable or learned. The two work differently, but in one respect they are the same: if a trait is beneficial to the individual, then it will spread, and the more beneficial it is, the more powerful it is, the faster it will spread. Whether magical/super capability was genetic or something a person can learn, in the real world it would spread like wildfire. Within a couple of generations, it would express in the normal (bell-curve) distribution across the whole however-many-billion of us, and it would be just like physical strength, intelligence, or technology. At that point when it had mostly taken over, the shape of civilization might be radically different, but human nature would still be the same, so the overall prevalence of evil and good would be the same. During the transition, the great evil would clash with the great good, and people would be forced to choose sides and do battle. There would be a lot of violence. Once the bell curve was reestablished, though, you'd have what you always have: 1% good, 1% evil, 98% of the population just following whichever side is most willing to do violence (usually the evil), most of the world would live under oppression as they do today, not happy but satisfied, convinced that any greater freedom would be scarier than the "normal" evils their governments impose on them or their neighbors each day, and that would last until the next upheaval.
But in any case, the idea that magic/super powers would appear in and remain, for any length of time, the exclusive domain of a select few is probably more unrealistic than the notion of magic/super powers itself. That's a pure writer's conceit, a convention which defies everything we know about how the world works.
We/They/People: The other thing that a debate like this sees a lot of us the use of collective words. One says, "
People would abuse their powers," because "
we humans aren't capable of wielding power justly." That might be true, in some sense, but no one ever defines "people" and "we" precisely enough to get to any meaningful sense. All these words really serve to do is distance the whole thing from "I". A much more interesting question to me than "what would the world be like" is "What would you be like?" If superpowers or magic appeared in the world, there's just as much likelihood that it would be you stuck with them as anybody else. How you would feel as a normie caught in the crossfire between two supers is an easy question, ripe for cheap cynicism. Anybody can write something cynical. All you have to do is blame everything but the protagonist for the problems and never solve any of them. That's how you get "The Boys."
I ask you, what would you do? If you were in that first generation, when superpowers were still rare, would you be corrupted by your power? The evil supers would immediately bring violence to the world, an ultimatum that all the rest obey or die. Would you have the courage to fight them? Would you have the courage to kill them? Could you do that without becoming them? Are you different from them, and if so, how?