Self admittance that you are not taking personal control over it, causing your being underweight. When you become stressed you're turning focus even more away from your diet, focusing instead on other issues, and begin unconsciously overeating. All the points leading to personal responsibility over your diet and the consequences of inconsistency.

Anyone struggling, and refusing to take the accountability to just flip a food container and check the amount of calories, is lazy. If you're comfortable with your weight, fine that's fair. But if you're unhappy, dealing with health repercussions, and wish for something better: put the work in. This idea that society as a whole is obese because of fructose (a sugar found naturally in fruit) or any sugar is braindead and would come from the same people who fell for "Eggs are bad because they have cholesterol". Uneducated, misinformed, and unwilling to learn or act, those are the issues. All solvable through personal growth and accountability, something sorely missing in this new cringe culture of being coddled. And in my experience/opinion, anyone unwilling to take their issues seriously and grow for themselves, aren't my fucking concern and they could die obese for all I care.

My own anecdotal experience was being overweight after highschool due to a reduction in my activity but no change in intake. I picked up powerlifting as a hobby and began to explore data, books, and videos by well known industry members like Mark Rippetoe and Dr. Mike Israetel regarding both training and nutrition. Since then I've successfully managed my weight the way I need it for competition by calorie counting and tracking how my weight responds weekly. Take this year: I'm 6'2 and in January was ~230 wanted to bulk, by June was ~270 decided to cut, now I'm 242.

Objectively the only way to not be obese is calorie deficit management. This is basic thermogenic energy balance science and the only people who seem to not understand it are the psuedo-intellectuals here that have never been active or done a sport in their life.