Blackrock and Vanguard don't own the money they invest for me when I buy one of their ETFs or CEFs (closed end funds). I still own that money and the dividends they pay me. If I buy a Blackrock fund it's because I believe it'll get higher returns than another issuer. Asset management capitalism has given me literally hundreds of alternatives to choose from. If I don't like the returns I get or Larry Fink's greenwashing on ESG, I can dump the fund and buy something else. Calvert, Working Assets and Parnassus offer funds with less greenwashing ESG.

Most people don't have the skill set to follow your prescription and still generate an adequate passive income from their savings when they'll be too old to work. Your advice is financially unfeasible for most people because it's not: scalable, predictable, simple to follow. Create a family, friends, community index fund that can be bought and sold in three clicks if you actually wish to see it gather sufficient AUM to make a difference.

Washing the greenwashing out of your money--decarbonizing it--is too complicated for most investors: https://medium.datadriveninvestor.com/decarbonize-your-money-its-not-so-easy-c11a4aecaef5