There are companies who will sequence your gut microbiome and give you actionable insights - full disclosure I work for one https://joinzoe.com/
Would inspire more confidence without hyperbolic claims. Or the auto-playing videos.
While the podcast is focused on female health, the advice applies to men as well.
More specifically: Why does being an epidemiologist qualify you to have an opinion on gut microbiomes?
Even more specifically: DO you have randomized, controlled trials to point to? Otherwise, this is just an argument from authority, and one who's experience is not clear is relevant.
Tim’s papers can be found here: https://scholar.google.com/citations?user=FIK--DEAAAAJ