So you mean calorie counting? This sounds easy, but in my experience it's very difficult to be compliant. You actually have to weigh your food and keep a record of what you're eating. And how do you do this when, for instance, you're someone's dinner guest and they've done the cooking? It's not impossible but it's a lot of work.
> you never learned to stick to your sustaining energy level when eating, you will go right back up again once you stop with something like intermittent fasting. Or do you really want to do that for the rest of your life?
I will tell you how it works for me. In general I get by with "intuitive eating" - in other words I just eat what I want, with some loose guard-rails in place, like I try to eat mostly whole-foods I cook for myself, and I try not to snack between meals.
I also track my weight daily, and when I see it start to increase beyond some normal fluctuations - which might happen, for example, during the holidays, or when I've been having more work lunches out than usual - I do intermittent fasting (essentially skipping breakfast) for a couple weeks to get things under control. This has been a very effective strategy for me for a few years now, and it doesn't take any significant effort or book-keeping.
Moreover, fasting is something which has been a cultural practice across the globe since the beginning of time. Many religions include ritualized fasting as a part of their practice, and I have heard Hindu people talk about taking a day off eating "to balance the body" as though it is a common-sense thing to do.
I'm not saying IF is the one and true solution to weight management, but I do not see fasting as more or less an artificial "fad" than portion control.