Let me put it this way.
I am an engineer. Most of medicine is an art, not a science.
I have seen such claims literally all my life. I am north of 40, and have seen few pan out.
The older I get, the more I remember what my grandpa told me with the last sea change was in full swing.
There is a reason we did things the old way.
DNA analysis is allowing the identification of bacteria that was impossible or very difficult in the gram negative/positive days. We’re seeing studies that are showing correlations between the gut biome and autoimmune diseases. As you said medical science is an art. It’s not a straight forward application of physics like engineering. We’re beginning to understand the universe that each of us comprises including about a trillion human cells and a hundred trillion microbiota.