I'd used email since about 1975, and it seems to me that 15 years of email is plenty for one lifetime.
Email is a wonderful thing for people whose role in life is to be on top of things.
What I do takes long hours of studying and uninterruptible concentration. On the other hand, I need to communicate with thousands of people all over the world as I write my books. I also want to be responsive to the people who read those books and have questions or comments. I have a wonderful secretary who looks at the incoming mail and separates out anything that she knows I've been looking forward to seeing urgently. Everything else goes into a buffer storage area, which I empty periodically.