Here’s a more scholarly way of expressing how (and why) Tolkien saw himself as a discoverer of legends rather than an inventor of stories.
“He did not see himself as an inventor of story but as a discoverer of legend.”
Blessed are the legend-makers with their rhyme / of things not found within recorded time.
Ars longa, vita brevis? Not for the Elves.
Later in life, he threatened to speak nothing but Old Mercian anymore!