Specifically, doctors prescribing GLP-1 meds counsel you on diet and exercise because it is necessary for the GLP-1 meds to be most effective, and "working out and eating responsibly" is not new advice to people who have been obese for a long time. Also, the moral judgment of "just need to work harder" is trash, and untrue. I guarantee you people who have been obese a long time have not spent their entire lives just "being okay with it." They walk into a doctor's office crying, not knowing what to do, at the end of their rope, or they have simply completely given up ever trying again because it has never worked.
Sometimes, it is laziness. It would be absurd for me to argue that is never true. But that is a tiny minority, and I would bet money on that.
You know what creates far more longevity? Not being obese, and working out and eating responsibly. Sometimes, in order to achieve that, some people need help; and we finally have some help in the form of these GLP-1 medications.
I'm not sure why anyone would be against people finally getting healthy.