While I get what you're saying I don't think this is what most people think of as "solved".

The brass tacks are:

1. Estimates for the cost of obesity globally are somewhere around 2 trillion dollars.

2. Telling people to diet and exercise usually did not get them to lose weight

3. Giving people semaglutide does get them to lose weight

So many people in my life who were unhappy and struggling with their weight are now happy because semaglutide worked where advice about diet and exercise did not. I can't imagine most rare disease drugs will have that level of impact.