Why is there an underlying assumption that FIRE means only slogging and stressing out until one actually retires?

I think Hritik Roshan’s example of a man slogging and working hard just to pocket as much money as possible till 40 and then retire shown in the movie ZNMD doesn’t represent the masses. Most of the FIRE aspirants are a working class who get the same salary (plus few extra perks if they are lucky which anyway are peanuts) regardless of slogging and stressing out.

For most, FIRE is not like working as hard as possible and get out of the rat race in few years, it’s all about a journey of a decade or two corporate life during which FI and ER is achieved by targeted savings and investment.

It’s not like slogging and stressing out because one wants to FIRE. In reality, one actually wants to FIRE because one is slogging and stressing out which he doesn’t like.