As a non-fat person who doesn’t exercise consistently, it’s not that simple for the vast majority. There are a lot of factors including health/genetics and the stuff mentioned in the comment you responded to. I’m not skinny because I avoid meals, I’m skinny because I lucked out genetically and I really don’t have to worry about what I eat in terms of gaining weight.
Also, avoiding meals is like the worst way to maintain your weight and you should stop implicitly recommending it. It’s just going fuck up your metabolism, nutrition, and ability to maintain your weight. Quality matters substantially more than quantity, and quality is prohibitively expensive for many.
Proper intermittent fasting is quite a bit more involved and planned out than “avoid meals”, and doesn’t seem to be what the other comment was referencing.