Rather it is about controlling expenses. The thing you can actually control. My sister's family of 5 lives on less than 50k CAD / year, because they simply must (low income) so if one is making a 100k white collar salary (for example) one can live a lifestyle higher than hers while still banking 50k/an. Etc.
There is a base level beyond which you can't save much, so first order of business is maximizing your income (e.g. better job/raise/promotion) without going bananas and sacrificing your health for it.
Plus the monthly insurance premiums. Financial independence without a large sum of money does not make any sense, and a large sum of money comes from either inheritance, or income.
Yes there is a floor to this strategy. If you are going to the food bank to feed yourself because you don't have enough income you're unlikely to be able to reduce expenses enough to make this happen. But if you're lower-middle-class or above it is possible.
With a small income, everything goes on necessities. FIRE isn't possible.
Personally, I'd love to FIRE. I have at least 5-10 years of personal projects in my head that I would do if I didn't have a 9-5 job. Unfortunately, graduating into a shitty 2009 market and not having nepotism connections means I am unlikely to ever FIRE outside of some expat poverty FIRE in a cheap country.