IDK about this article. I was reliably informed earlier today by a front page article that was certain that a gut bacteria's most important job was to do nothing.
(I apologize for the sarcasm, I know this isn't reddit. This is one in a growing number of interesting results about molecules found/created in the gut by bacteria. a previous article today was an idle musing about bacteria in the microbiome having the key job of not being worse strains of bacteria [like c. diff] without much other role)
This is actually a well written no-hyperbole representation of interesting original research, makes no generalization. So your criticism might be misplaced.
The alternative hypothesis you discuss is not necessarily mutually exclusive with the findings in this research though. It all depends on what microbes you define as harmful, though at that point why even bother with the original generalization anyway?
(I apologize for the sarcasm, I know this isn't reddit. This is one in a growing number of interesting results about molecules found/created in the gut by bacteria. a previous article today was an idle musing about bacteria in the microbiome having the key job of not being worse strains of bacteria [like c. diff] without much other role)