I was looking for something to justify elves being able to put up a fight against humans despite the human number advantage.
Then you should have stuck with actual advantages the Altmer displayed rather than some trumped up racial superiority tripe.
Such as superior preparation and tactics during the Great War. They put out the Empire's eyes then syphoned off a great deal of its strength before they ever made their move. They acted decisively, taking advantage of the Empire's complacency and confusion to win early, important victories. They also put the Empire into a situation where it had to sacrifice parts of itself for relatively short term victories.
The elves got what they wanted because they targeted specific weaknesses and, with some glaring exceptions, fought a smart war.
And while that is admirable, it is hardly a uniquely Altmer trait.