Hell there are memes about the old dude TRT being the fittest he's ever been and being able to crush your gains comparatively
Longevity is activity, understanding your BRM, and extra if you aren't seeing results is microbiome stuff like eating foods that don't mess with your micro biome like artificial sweetners.
As an aside: I doubt many people will trust this but if you're all about your micro biome and found there isn't much science around your specific scenario are willing to try weird things, try going off what's recommended for your Ayurveda types. Which is surprisingly finding traction in other aspects of psychology and nutrition but still very early. Just drop the spiritual stuff and take that as what their explanations why there are results from diet effecting mental health and a way to preserve it over this many generations