system
Given the following post, respond as if you're commenting on Reddit:
human
[Lord of the Rings] Why was there such a huge discrepancy of power between First Age and Third Age?

Even Gandalf was afraid of Balrog, a terror of First Age, why is this? Was everything in First Age better? So the world is always....devolving?

Please explain.
gpt
Yes. The story of Middle-earth is the story of magic leaving the world and the fading of the Elves to give way to the dominion of Men. The Elves and Men of the First Age were considerably more powerful than anyone in the Third, even Aragorn. The glories of the First Age like the Two Lamps, the Trees of Valinor and the Silmarils could not be recreated by even the Valar. Also, fighting a Balrog was a dicey proposition even for the most powerful in the First Age: they're fallen Maiar, angelic spirits from before the beginning of time that were corrupted by Morgoth. They could only ever be mastered by the most powerful, and even that was no guarantee: Feanor took on Gothmog and lost. Gothmog and Ecthelion fought each other during the Fall of Gondolin and it was a mutual kill. Likewise for Glorfindel and the Balrog he fought while protecting the refugees from Gondolin.