I'm nearly 50 now and after being burned several times I made a vow to myself never to be dependent on anyone else again. Even if you work for an incredibly well-funded company, that doesn't mean some dweeb with an MBA in some office in another city / state / country won't wake up one day and decide to wipe our your entire division just because she needs to make a bigger bonus.
I've seen pensions disappear overnight, industries collapse quicker than anyone ever thought, and vibrant cities crumble when big employers shut their doors. Painful and stressful in the extreme.
I've also blown $10k on something stupid instead of buying another bunch of Apple stock, reasoning that I'd make it up later in life easily enough. That was 1997. The $10k would be well over $1 million now.
The biggest thing to learn is that money doesn't equal happiness. That, for me, is the repeated lesson of MMM and related authors. Freedom to make decisions without reference to finances is a massive, amazing thing.
There's an active community on Reddit at https://www.reddit.com/r/financialindependence/
One point that often comes up is that people shut their mouth about FIRE because if they bring it up, the reaction is often negative. There might be several people you know working towards FIRE but they don't evangelize it.