Bitcoin is a drop in the ocean in terms of energy consumption and the release of greenhouse gases. Last year, streaming online pornography accounted for over 30 times more greenhouse gas release than the entire bitcoin network and all bitcoin mining did. With so many people currently on lockdown or quarantined within their own homes, that number is going to be several multitudes higher right now. While we get posts on here at least once a week saying that bitcoin is doomed because it isn't environmentally friendly, I've never once seen climate change campaigners try to convince people to watch less porn, even though it is by far and away worse for the environment than bitcoin is. I've never once seen climate change campaigners try to convince people to stop using cash, despite cash requiring huge amount of energy to print, circulate, move around in armored vans, destroy, replace, all the electricity use of ATMs and banks, etc.
Bitcoin is extremely efficient for what it does.
Millions of people worldwide are using their PlayStations, Xboxes and such, and no one cares.
Yup. Factoring in the electricity consumption of games consoles, TVs, sound systems, and PCs, it absolutely dwarfs bitcoin. Making video gaming 1% more efficient would save more energy than the entire bitcoin network.