There has been plenty of literature about bitcoin effects in the environment. While I agree that bitcoin is probably less damaging to the environment than 20 thousand Visa employees commuting to work, there is still plenty to do about the farms and the energy they consume. It may be possible to support green mining over others?
You have to also consider that this comes with some degree of hype with it.
Not all "sustainable" companies are actually doing much better than what traditional companies are doing. They may simply be better at cooking the numbers/their books to reflect a much prettier version of reality.
I'd definitely include ESG as a part of a portfolio, but I would not invest all of my portfolio into ESG stocks.