There are over 10,000 farms that have been actively using Holistic
Management practices for over 20 years.
Their longevity suggests they are earning a sustainable
livelihood, and I would venture to guess most holistic contexts include some form of Earth Care (building resilient
ecosystems) and People Care (building quality of life).
What's more, HM uses standardized documentation.
So, potentially, there is a MASSIVE trove of (essentially standardized) information about regenerative agriculture in the financial documents of these 10,000 farms.
Darren Doherty keeps imploring someone to put together a study but as far as I know no one has taken him up on it.