I always thought of Charms as a fundamental expression of a character's skill and power and as distinct magical techniques that two Exalts might be able to cross-compare. I didn't find it that hard to reconcile.
The way I conceived it, the human body has a set of movements it's theoretically capable of performing; you can't bend your knees backward (without some helpful assistance from that moneylender you're in debt to), lift your legs above your head, et cetera. Some people can't curl their tongues or wiggle their ears or raise their eyebrows like Spock. The set of movements that I, the dude writing this, can make is a set of movements I've learned that rise out of my experiences and skills, and I can improve and learn new ones as long as they're within the body's theoretical limits.
Similarly, the Essence within an Exalt has a set of "movements" it can theoretically make. It has certain limits -- you can't shoot your mouth out on a tentacle or curse someone with bad luck to the seventh generation if you're a Solar -- and certain kinds of "movement" that are easier for it, just like it's easier for most humans to balance on two legs than on one. The skills and experiences that an Exalt undergoes and acquires, the training and discipline they practice, allow for certain forms of Essence to manifest, and while they're individual to each character they're still recognizable between characters. (Similarly, nobody's going to mistake my Spock eyebrow for Leonard Nimoy's, but it's recognizable as the same gesture.) Because Exalted is a grandiose world, people have named these techniques -- Charms -- where they haven't named individual muscle movements, but in my view, the theory's kind of the same. Because there's a metaphysical component, the use of Essence, I would call Charms a form of magic, but I guess I can see the logic of reserving that specific term for sorcery.
This is all valid, reasonable, and interesting.
Whether you see it your way or mine won't change how the Charms work mechanically.
But a Solar who just Exalted in Nexus can complete the entire Dawn Charmset without ever meeting another Solar, without knowing what the Solars were/are, and without any exposure to First Age lore or past lives.
The Charm set is not external, waiting for him to discover it. So he has no idea what the names of any of these Charms are. He exists in a complete vacuum, and the game supports thisâ€”if he is a Dawn, he needs no training. If he can learn the Charms without training, and can learn the Charms without knowing their names, and is not automatically Exalted with a full codex of Charm names (which he is not) then you might conclude that the "Charms" (he may not even think of them as Charms) he has learned have completely different names and methods and pathos from the exact (mechanically) same Charms of another Solar, regardless that these two Solars were modeled by the same Charm set, the same mechanics, the same names.
IE, the names of Charms, and even Charms themselves don't qualify as anything important or crucial or necessary. They are just character descriptors. Your character can learn them without even knowing their names!