"Companies go to great lengths to set up lists of authorized approvals, meaning who can approve what size of purchase. But you will find that people who are not authorized to spend $100 on their own are authorized to send e-mails to people and waste hundreds of thousands of dollars’ worth of company time."
I don't think we'll be removing people's e-mail sending privileges in the workplace anytime soon, but it would seem sensible to have a means to pare down mailing lists to those people who need, or want, the information in the e-mail.
I'm not talking about jokes, personal messages, or fyi courtesy-type messages, since those are necessary, and proportionately speaking not real time wasters, compared to some work-related messages.
It's those work-related messages that you skim through asking "what is this?", "is there something here I need to know?", "is this person asking me to do something?", "why did I get this...?", "do I need to send this to someone?", that are time eaters. Generally these e-mails are sent to multiple people...sometimes hundreds of people and come from people you don't work with on a daily basis - making it challenging to understand the context, urgency, or real issue that the email is trying to convey.
I don't think there is any solution to this other than at the receiving end. You have to learn ways to skim information for what's important and move messages out of your inbox, and into folders, quickly to make room for emails you need to be effective at your job.