fair enough. Focusing on the FI and not the RE can be a good compromise.
Realistically, passive income is more easily achievable than living frugally.
This resonates with me, very much.
You keep talking about financial flexibility, which is great, but that's not FIRE. The FIRE lifestyle has a clearly defined goal: retire early. When one sets that as the goal and doesn't reach it, that is considered failure. That doesn't mean nothing good can come out of the pursuit.
Personally, the "idea" of FIRE has always appealed to me, but I also think it's not an all or nothing approach.
As
@Lurker and others have correctly pointed out, to achieve "true" financial independence and early retirement requires earning large amounts of money (ideally as young as possible) while at the same time minimizing your expenses in order to save as high a percentage as possible - both requirements which, while (IMO) not "against" Torah values, don't really work with a frum lifestyle today (where we mostly marry young, be"H lots of kids, not necessarily working high-paying salaries). The financial investment in children in particular is a significant point which many FIRE bloggers and evangelists are quick to highlight (and oppose, or delay until much later in life).
But for me, the goal of financial independence doesn't equate full early retirement. The point is to give me independence to live my life the way I want - while not being locked in to a full-time job (even one I enjoy doing) for the next 30-40 years in order to support my family.
I would love to take a year, or a few months here and there to spend traveling the world with my family. Or to spend a few years working part-time (or not at all) in order to spend more time learning. That is my personal "goal" with regards to FI(RE). As mentioned above, I too don't see any value in early retirement just for the sake of "retirement".
With regards to living below ones means, and trying to achieve a higher savings - I truly think that's just smart financial behavior that everyone should be aiming to achieve, not only diehard FIRE.