Watching videos for entertainment instead of working on solutions to global warming and/or new metamaterials that are created from carbon neutral sources such as biodiesel (with the use of your computer) is a setback towards the goal of carbon neutrality.

We are about 10000 steps away before worrying the power usage of websites. Transport and energy generation changes are many many order of magnitudes more important

We have much larger problems to solve than Wasm. E. g. Java. 2 billion devices run it!

That depends on how "dirty" your electricity is, and maybe on how much dirty energy your clean energy could have displaced? My laptop runs mostly on nuclear power with most of the rest from some kind of "renewable" energy.

I don't understand