For my sins, I was taken down the rabbit hole of a document called "The Carbon Impact of Web Standards" (no, I'm not linking to it).
Friends, I feel nauseous. I'm getting dumber just leaving this tab open. Does it start with a situated analysis of the potential contribution of web content to overall GHG emissions? Lol, no.
Nor does it start from any estimate of real-world site construction (e.g., via the HTTP Archive).
It's so, so much worse.