Elon Musk is a hater of ESG. So is Peter Thiel. And, increasingly, so are executives and bigwigs who work in the industry surrounding environmental, social and governance investing.

The ESG ecosystem is a market worth an estimated $4tn, which is a big pot of money for an industry so nebulous and murky. Many have asked, what legitimately counts as ESG? Can the ESG label be slapped on things that aren't helpful, even harmful, to the climate? In other words, there's a lot of greenwashing.