Many critics of Herbal Medicine say there is no evidence as medicines. So I did a search on PubMed on 24th of April 2021 of individual herbs and of a few general categories just to see how much research has been done into herbs and herbal medicine.
The top fifty herbs that Vitawell uses in their dispensary there are 176,262 papers on PubMed the list is above.
"Herbal Medicine" as a search resulted in 51,136 papers.
"Herbal Medicine Cancer" has 7,104 papers.
"Natural Medicine" found 321,739 papers.
"Nutritional Medicine" found 172,343 papers.
Of course not all of these papers will have positive results however a significant proportion do add understanding of herbal and naturopathic medicine.
https://pubmed.ncbi.nlm.nih.gov/?term=Herbal+Medicine