I came across the FIRE acronym relatively recently recently and my first thought was ...errr,,isn't this just the game of life everyone plays? Then it occurred to me , nope, it isn't , and that prompted another thought. Why isn't it ?
That such a "tribe" has coalesced, is probably a function of the internet/social medias ability to connect people with greater speed and ease these days, and of course every tribe needs a "flag", so an snappy acronym was inevitable.
However, I think there is more to it than that, I think it's a bit of a tell as to what is generally missing in broader education and social conditioning.
Formal schooling is sadly remiss in omitting basic financial education, the working of the world of resources are a closed book to many, so movements like this can be a bit of a light bulb moment.
Add this to the general conditioning to mindlessly consume, the all pervading psychological assault by the media from every angle that undermines rational thinking with monkey-brain triggering, and I can see how a movement like FIRE would seem to be a "big thing" to many, when as you say, prudent planning, long term goals and a desire to safeguard the future are ideas that are as "old as the hills"
RE: FIRE