Also, when I send an email to my friend "laserpants@something.com", sure the data captures the send-to email address. But the data doesn't know who laserpants actually is, nor does the email content get saved. I'm not saying laserpants can't be found if the law decides to investigate, but I doubt it's a matter of pressing a button to bring up the real name of laserpants. Especially if laserpants uses different email addresses and a shared internet.
If your friend uses a separate, privately maintained email address for everyone and every service, that will help a lot. Then we only know his identity because email is sent in the clear, even between his own server and home computer. Of course, everyone uses separate email addresses for everyone, right?