Yes indeed - Gene Roddenberry wrote the lyrics, knowing they would never be used.
Why? Easy - by doing that he claimed 50% of the fee for the theme tune. Alexander Courage (who did the music) had it in his contract that every time it was played he got royalties, as would any lyricist. So by doing this, Roddenberry took half of Courage's fee. For decades, Roddenberry took half of his cash.
Courage was, to say the least, unhappy about it.