Earlier quoted context omitted.
Prescriptions of diet and exercise are ineffective because many obese / type 2 diabetic people can't exercise self-control. That's why they're obese in the first place. It's way easier to take a pill than cut to 1500 calories a day for 2 years.
It is a harmful stereotype to label obese people as lacking willpower as you have done. Many obese people don’t have the resources (time, money) or tools (nutrition understanding) to improve their situation. Many have metabolic or familial history of obesity which has both physical and psychological (normalization) impact on their ability to control their weight. The former can be helped with diet and/or medication,…
Most cities and towns have little walking or public transportation. Cheap, high-calorie, nutrient-poor food is easily available anywhere 24 hours a day. Restaurants have an abundance of large amounts of meat and carbohydrates drenched in low-quality oils and sugary seasonings.
You have to be consciously active to stay fit or cook the majority of your own food. People in a lot of other countries stay lean and aren't as obsessed with fitness as we are.