What we are saying here is that you reduce your calorie intake within the range where gut bacteria can act, it might not have any effect, or even negative effect.
If you reduce your calorie intake below the level gut bacteria activity matters, you will lose weight, but only if you can sustain the diet for basically the rest of your life.
If the diet doesn't fit you, you will be fighting your body every single day, and your body might cave in and it becomes your new norm, or you can't stand it anymore and go back to your previous behavior.
Fighting your body until it gives up is such a brute force method it's just hell on earth (we say "your body", but litteraly you're punishing yourself). Experimentally the vast majority of people won't be able to brute force their behavior And metabolism, and have to find a diet that fits them. S
What I'm saying is sustaining low calorie intake is a result of having a diet that works. The relevant part is to find that diet in the first place.