I don’t agree. They are not saying that.

It’s observational. They are saying they see correlation.

Your suggested mechanism is plausible, and likely, of course, but that might only be part of the effect.

I think it’s still valuable findings and can help direct further studies.

Whether or not this is the case for this particular study, I wouldn't be surprised if they end up being miracle drugs that reduce everything from heart disease to liver disease to cancer through weight loss and reduced alcohol consumption.