As has been pointed out elsewhere in this forum, infections, immune system, mitochondria, oxidative and nitrosative stress, etc. can all play a role,
I think their hypotheses are the core issue in ME/CFS. Will there be subsets of people that have other issues or additional infections etc. to address, almost certainly.
I don't think that negates their hypotheses, that the gut is the core issue.
He recommended I use glyphosate to restore my microbiome, so I'm a bit skeptical of his suggestions.