The point of ESG investing is to lower the stock price and raise the cost of capital of disfavored industries, and therefore slow down their investment. It's a form of boycott. The cost of capital is the expected return. If it works, it raises expected returns of disfavored industries, and lowers the expected return of favored ones.
Yet ESG advocates claim that you do not have to trade return for virtue, that you can even make alpha by ESG investing!
If that is the case, it means ESG investing does not work! Take your pick.
Why do ESG advocates care? It seems perfectly normal to say, "Look, this little boycott is going to cost you something but it's worth it to save the planet and other social goals." The problem is, most funds are handled by intermediaries who are not allowed to lose a little money on your behalf in return for their idea of virtue, for the simple reason that it may not be your idea of virtue. A mutual fund marketed this way cannot sell to a pension fund, even if the mutual fund and pension fund managers all agree completely on what environment, social, and governance criteria are valid, because neither knows that the recipients of pension fund money have the same preferences. Our laws and regulations occasionally do make some sense!
But if you don't lose money on ESG investing, ESG investing doesn't work. Take your pick.
(HT, thoughts resulting from Jonathan Berk and Jules van Binsbergen's paper on ESG returns.)