I think they said all they legitimately could. “Reverse symptoms” or “reduce symptoms” might have been better.
Without doing brain scans, which they can’t always do - my father couldn’t have one because of his heart pacemaker - they can’t say they’ve “reversed” the organic development of Alzheimer’s. All they can say is that some test subjects’ symptoms improved.
If these results are as reported, it will be beneficial for some. Sometimes nutrient-deficiency is an issue for the elderly. My father improved for a while, early in his progression, when he began getting Vitamin B-12 shots.
There can also be psychological knock-on effects from the perception of memory loss. One believes that one is losing one’s marbles and it becomes self fulfilling prophecy.
That, too, can effect brain scans.