Your post caught my attention. I agree with this view on gut.Only Probiotics wont help you that long. You need them only as a "starter"
Good gut bacteria wants to be fed. Without food bacteria is back to old count in 2 weeks. With soluble fiber the good will increase on its own.
So you need to eat lots of soluble fiber that can be fermented like inulin, pectin, resistant starch.
Fiber like psyllium husks (insoluble fiber) is more to increase stool volume + clean out the gut of bad bacteria / endotoxin. (Ofc some good go with it) Ray Peat recommends Carrot salad for that.
Good bacteria (esp. bifido,prausnitzii and lactobacteria) will fight badbacteria / endotoxin if you got enough of it. + rebuilds your epithelial layer and intestinal barrier ! (by producing Butyrate)
I know lots of people on here do have the idea of having low as possible bacteria count in the gut. But thats just not right. Sure low endotoxin is good. But if you have enough "good" bacteria it will help you to stay in a good homeostasis to keep "bad" things (bacteria, pathogen) from increasing.
@Madato Very good tips! One thing I wanted to ad with my text is the difference between fermentable / unfermentable and soluble/ unsoluble.