One thing which I would like to highlight is the importance of habits. Prior to my retirement (<2020), the people around me in their 40s/50s usually will have meals at canteen/food court. One typical lunch can be like S$4 with a drink S$1.20. For a typical day, the expense of eating out is <S$8. I think most of us are doing OK, already FI/semi-FI.
Now that I rejoined the workforce, my colleagues who are more junior, are mainly in their 20s. Every lunch must be in restaurant ('cause YOLO, so must enjoy life -> their logic) S$40++, this is followed by bubble tea (the fanciful) which is like S$8 or S$9. One typical meal is typically >S$50. The funny thing is most of the time, the restaurant food is so so and we have to waste time queuing for seats. These are also the people who talk about crypto, US stocks days in day out (and are bleeding).
With their way of handling and spending money, it is almost impossible to achieve FI.