I often have this image in my head. I'm ever walking through a door and into a room loaded with infinite doors. As I choose yet another door the room collapses into a single doorway which opens up to a room with infinite doors repeat until you walk into a room containing literally nothing.
Frankly regardless of FIRE this image is true just as a function of how time flows and reality and I'm probably losing people at this point....
But how it links to the discussion is that you have some agency in choosing your path (regardless if you actually do or not, you should behave as if you do). That agency allows you to choose a path which contains meaning (if that is something you value and helps drive whatever goals you might have), or not (if that is something you value and helps drive whatever goals you might have).
I like something rebs has said, which I may be paraphrasing or accidentally plagiarizing, I'm just here to reduce the inevitable growth of entropy. Remember entropy is just useless energy which produces no work and can't do anything.