You are wrong. This paper very clearly does not show that it "works". The debate exists for a good reason - the very thing this paper claims to show is the exact thing the person you replied to was questioning. And that is a central question in all of Alzheimer's research.

There are dozens of studies that show mice improving their memory/spatial reasoning as Alzheimer's models. None of them have led to a proven improvement in longevity or quality of life for human Alzheimer's patients. Some of them slightly slow the progression, but even then you're getting into a gray area - is it really "better" to be stuck in the Alzheimer's fog for longer? Are we actually improving quality of life? It's unclear.

So no, in order for us to say that this approach "works", we would need randomized controlled clinical trials in humans showing a strict improvement in quality of life and/or longevity. This is not even close to that level of evidence.