system
Given the following post, respond as if you're commenting on Reddit:
human
[Lord of the Rings] How would the Fellowship's journey change if Gandalf the Grey survived Moria?
gpt
Odds are high that Gandalf wouldn't have the power to remove Saruman's control over Théoden.  That would mean that Rohan would be completely removed from the equation and most likely destroyed by Saruman's Army.  Without Rohan's assistance at the Battle of Pellenor Fields and the addition of Saruman's Army, Gondor would most likely have fallen to Sauron's Armies as well.  Even if Gandalf got the Fellowship into Mordor and destroyed the Ring, the devastation wrought by Saruman and Sauron's Armies would have brought an end to the Kingdoms of Man.

Also it would be unlikely that Merry and Pippen would wind up in the company of the Ents.  If they aren't in a position to convince the Ents to march on Isengard, then Saruman's power base remains intact and his army able to be reinforced.