Pick a magic spell that isn't mentally oriented, and I can do something towards that without magic -- perhaps not at the same scale or effect, but I can try. Fireball? I can use oil and fire, or alchemist's fire. Weaker, less effective, but I can do this. Fly? I can climb to high buildings and construct wings, or ride a griffon. Invisibility? I can try to hide or camouflaged myself. Magic in other areas does do magical things, usually by expanding the scope of the effect. But, I cannot convince an NPC or PC of a thing if they don't want to be convinced outside of Charm Person. Flatly, if the GM says, "this guard will not let anyone unauthorized past," I cannot talk my way past him, no matter what, with freeform RP but I can Charm or Dominate him and do it. My only option is to try a different approach. Thus, "it's magic" doesn't even hold water compared to other magic when it comes to Charm. It's a totally weak argument that sums up to "because."
This whole line of complaint about charm/domination magic makes no sense. In fact, it makes so little sense it is
nonsense. It is just as much "because"-style circular reasoning as what you are complaining about.
Magic in most TTRPGs isn't just extending nonmagical things. Or, put another way, you
just aren't "do[ing] something towards" a magical effect "without magic". Magic, more often than not, breaks fundamental rules of reality. You
just aren't replicating
fireball when you use alchemist's fire. Alchemist's fire is a fueled chemical reaction.
Fireball is "
manipulat[ing] thermodynamic differentials with your fingers". Constructing a glider/artificial wings is manipulating known forces to stay airborne. The
fly spell is telling those forces to shut up and sit in the corner. Hiding or using camouflage is about staying out of other creatures' line of sight or being mistaken for something else. Becoming invisible magically entails letting light just... pass through you unobstructed (despite your own eyes still receiving light in sufficient quantity to see by).
Why do werewolves or vampires have only particular weaknesses (varying from system to system)? There's no sensible reason for these phenomena that you can extend logically or reasonably from nonmagical principles. If you transform, say, a human into a toad, where does all their extra body mass go? There's no sensible nonmagical phenomenon that you can work from. How do dragons exhale fire, much less lightning or sleep gas? There's no good reason - it's just magic. (Although that one
faux documentary tried its best, bless it.)
Many (most?) varieties of magic in TTRPGS require overlooking physical or biological impossibilities. They are by nature inherently unreasonable. You can't sensibly justify them through any means other than "it's magic" because
there is no other justification.
Suffice to say, there is no sense in complaining about the circular nature of magic, because its very impossibility precludes any other nature.