"Its estimated that spam consumes more than 33 billion kilowatt-hours of electricity every year, the same amount as 2.4 million homes. It also produces the same amount of green house gas(GHG) emissions as 3.1 million passenger cars."
https://www.techbusinessnews.com.au/does-email-spam-affect-the-enviroment/
The average office worker receives around 144 irrelevant messages per day, of which 24% have attachments. Email attachments sent in copy are accessed only 6% of the time.
https://www.mxhero.com/post/save-the-planet-replace-email-attachments-with-file-share-links