Sauron's goal and the Dagor Dagorath

[Mister Underhill]

Annihilation of life as we know it would, I repeat, not be S.’s goal. Where is the evidence, even remote, for that? (The Old Man)

"It is an army bred for a single purpose: to destroy the world of Men." (The Lord of the Rings: The Two Towers [theatrical release] 1:58:11)

Since this post-dates the HoME X you quoted by nearly fifty years, I think we can all discern which is more authoritative. Put that in your pipe and smoke it.