I would push back and say that a lot of people didn't actually know that. They came up with elaborate reasons why eating less doesn't work, but keto works, or paleo works, or eliminating sugar works, or vegan works, or it's just physically impossible to lose weight.
"Eating less" as a strategy for losing weight is like "make a lot of money" is a strategy for becoming rich.
It certainly works, it is just an unhelpful strategy.
Keto changes the way you feel about eating if you enter ketosis for long enough.
Fasting does too, for that matter.
Paleo is just trendy keto with some woo on top.
The don't use the same mechanism as glp, nor do they have same success rate, but similar idea.
Eliminating sugar makes it harder to consume a 64oz soda at 800 calories in 3 minutes and still be hungry.
Anywho, most diets achieve some weight-loss.
But! keeping your mind and body from demanding you eat more to return to homeostasis is actually the 2nd hard part, and the part that most people fail at. And we'll see how much glp losses are sustainable (without shots) here pretty soon.
Regardless, this technology is good and we should subsidize everyone getting to a healthy weight. Searching for reasons they are actually morally inferior or stupid is counterproductive.
I agree sort of, but the argument here is do the simple thing, like "eat less". There; we're done - ha! My initial reaction (and also with the chose boring tech) is that's not the solution, that's where you start LOOKING for the solution! So boring is great, simple is fantastic - from a position of understanding. Too many people jump onto any "new thing" - diet, technology, whatever - because it's easy and right in front of them. Simple is often neither.
I would push back against your pushback and say nearly everyone knows that, it's just the brain is great at making excuses when things are physically difficult.
They did that because the other thing didn't work. It doesn't matter that the reason it didn't work is that they can't do it: the implication is identical.
Don't underestimate how impossible it can be to force your own body into a new behavior pattern.
I am constantly arguing with all of my friends and family who believe primary way to loose weight is to exercise more.
Exercising is great, absolutely, but eating less is the actual primary method. While acknowledging complications of metabolism and psychology and weird states body goes through when it's hungry, primary part is to reduce calory intake vs expenditure.
So as snide and silly as it may be, in my neck of the woods, I would agree, lots of people don't believe eating less is the primary method of losing weight.