> that last one is the most important for long term results

Empirically untrue. GLP-1s outperform diet and exercise alone.

> it's not like you couldn't combine a GLP-1 drug with great diet and exercise

This is how it's recommended to be taken. I personally know folks who were able to start regularly exercising and eating healthily because of the head start GLP-1s gave them. (They're mostly off them now, and they're all materially lighter and healthier than they were before.)

Diet and exercise guidance is the standard of care for prescribing GLP1s.

But prescribing diet and exercise alone has long had mixed results, because it does nothing to address appetite, and it is even quite common for exercise to increase it.