You could perhaps point to research that supports your claim? Would be better than simply talking down to people who disagree with you.

For instance:

Obesity is mainly caused by imbalanced energy intake and expenditure due to a sedentary lifestyle coupled with overnutrition. - Source

The obesity epidemic has been fueled in large part by increased energy from greater availability of highly rewarding and energy-dense food. Diet and various social, economic, and environmental factors related to food supply have a significant effect on patient’s ability to achieve the balance. - Source

Most researchers also agree that obesity is an “acquired” disease that, heavily depends on lifestyle factors (i.e., personal choices), such as low rates of physical activity and chronic overeating, despite its genetic and epigenetic influences. - Source

Sure, I agree but eating habits have little to do with weight.

I'm sorry, but there is a very great disparity between this statement and reality.

I agree somewhat with your post but this comment is utter nonsense. Diet has everything to do with it. Calories in, calories out is an immutable fact. The law of conservation of mass. However, not all calories are equal.

Obesity IS unhealthy. There are no two ways about it, but people just blame the individual, saying you just need to eat less, or or exercise more, are genuinely stupid.

There are many root causes. Modern diets are absolute garbage for one. Mass production of foods, fast foods, sedentary lifestyles from young ages, poor eating habits, etc... has absolutely fucked a lot of people.

Cravings can be addictions.

The body can quite literally work against itself. The brain can be so self destructive (which seems so ironic to me).

The world compounds that by creating body dysmorphia, either through transphobia, or celebrated body types that are unobtainable without great genetics and constant training (whose got time for that, do I really need a 6 pack?).

You don't need to be fit to be beautiful, but don't conflate that with "obesity is not unhealthy", because it is.

Extra weight on your your hips and legs will wear them out quicker. It pushes on your lungs and makes it harder to breathe. It makes your heart work harder to pump blood throughout your body.

I know from personal experience. It was terrible.

High cholesterol, high blood pressure... these things WILL kill you.

Being a healthy weight, everything just feels better. More energy, moving around, getting up, sitting down, I go on and on.

My point is:

People are fat phobic and super fucking ignorant about it. There are.mamy causes, and sometimes people get given a really unfair dice roll, both environmentally and generically.

But obesity is still unhealthy, and if you are obese, I hope you can find something that works for you.

I agree with your overall message that "most modern diet advice comes across as more insulting than helpful" (at least that's how I interpret it), but this reply isn't doing it for me.

eating habits have very little to do with weight

Source? "Calories in, calories out" gets repeated to the point of redundancy during conversations like this, but it's really all there is to it. If you consume more calories than you burn, you'll gain weight, and vice-versa. The exceptions to this rule are so rare and medically-anomalous they really don't fit into such a broad conversation as this.

And being overlyskinny or dehydrated to the point where you have no fat and can see muscle is more unhealthy than being out of shape and fat.

Again, source? This is also the extreme opposite spectrum. No one (worth listening to) is saying that this is preferable to obesity. What you call "fatphobia" is only so common now because obesity and obesity-linked pathologies is the most common cause of death in America. It makes sense that more people would be focusing on curbing these deaths than focusing on something that, speaking candidly, affects a much smaller percentage of the population.

The problem is our society has these ideals that are unachievable by most individuals. There are people out there who can have abs without effort and those who never can, but our culture doesn’t account for that and always views the skinnier person as healthier. We have never been good at catering towards individuals.