Wouldn't taking GLP-1 agonists (for potential non-weight-loss benefits) be potentially harmful as it may reduce eating even further and lead to being significantly underweight?
Almost certainly at the weight loss dosages people are taking now, but semaglutide (at least) can be tuned up and down for effect. Time will tell what kind of dosage is required for these non-weight-loss benefits.
That said, I think it's more important to focus on how this drug works -- it works in the brain and in specific areas of the brain that we now know are important for weight loss/addiction/inflammation(?) (because of these emergent miracle drug effect). It doesn't seem outside the realm of possibility that drug companies will be able to target these systems with more finesse in the future as opposed to superdosing engineered stable GLP-1 molecules that flood the system.
It is the future understanding of what this drug does that is the real promise for all people -- we are just in the early stages of understanding what we've found.
But that puts us back in the "telling people to exercise doesn't cause them to actually do it" at the public health level. For you yourself, you can simply live a less risky, healthier life. For all yous, probably we need something like a once-weekly pill or injection that doesn't require drastic habit changes. For all of society on a forever timescale, of course, we can ignore the fact that adults won't change their ways and focus on instilling lifelong athlete habits in kids. Doesn't seem to be the direction we're going in, though.