You may begin your argument now

There is no god. So I argue that medicine is at least just as potent as nothing.

Maybe ... maybe not.

Modern medicine does have magic pills for many illnesses; for example, antibiotics are magical for many bacterial infections, many vaccines are almost magical too.

OTOH, many pills will have undesired side-effects, and the body is in a complex dynamic equilibrium, so it may happen that blocking GLP-1 may have side effects.

Eventually, we'll all die, but I'm optimistic that GLP-1 will lead to a better equilibrium. Preliminary evidence says it will. I'm not as confident as the author though :)

You're right, but the way you're going about it isn't.

Any single pill? Or is your objection specific to this one? (That iirc is actually an injection, not a pill, but w/e)

You don’t believe the medicine that billions of people take to treat diseases that would’ve otherwise demonstrably killed them is “accumulated knowledge” enough? From insulin to antibiotics, we have sufficient evidence that many types of medicine DO work. Nobody is “playing god” (whatever that means), it’s just reproducible and consistent data