The client I work for is a peddler of health foods and supplements, so this kind of thing has been part of my daily life since I started the current job in October 2018.
The science is fascinating, especially the stuff about the gut-brain axis, but I’m sceptical about a lot of the “probiotic” products that are sold on the back of it. Still, it keeps me in a job, so I’m happy for people to keep buying them.
If an Ayurvedic diet has any health benefits, that’s largely fortuitous. As with any restrictive diet, you also have to be careful not to miss out any essential nutrients (B vitamins, iron and choline, for example).
The simplest way to support gut health is to eat lots of fibre (which is more or less what it says in the piece).