A few years ago, I carefully backed up my Thunderbird e-mail files and then completely deleted all the e-mail in my inbox.
I never once went back to that backup. Big lesson there.
Then a year or so ago, I bit the bullet and switched from Thunderbird over to Outlook 2016, again starting my e-mail collection from scratch. My web hosting service (Hosting Matters, big plug for them) has a great spam filter that reduced my incoming spam to about 10%.
I still get far too many e-mails, and my inbox is back up to ~3500 e-mails, dating back to July 2015.
I should note that I've got several filters to send e-mails from specific clients to specific folders, and I do some manual copying into folders as well. Yet I still have 3500 e-mails in my inbox.
I'm willing to bet I could delete the entire inbox and never miss any of them. But I think I want to do one last pass through before doing so.
This is going to sound smarmy, but I honestly cannot imagine just not answering or at least evaluating my emails as they come in. Absent some major crisis, it would kill me to have potentially important communication just hanging out there. Don't you worry about the message you are sending (pun intended) by ignoring people's attempts to communicate? You might not miss the emails you delete, but others certainly will miss your responses, especially team members and people with whom you actually have existing relationships.
How common is this (non)communication style? I'm honestly curious.
"I honestly cannot imagine just not answering or at least evaluating my emails as they come in."
Emails that I can dash off an adequate response to get addressed immediately. The killers for me are the ones that merit a thoughtful reply, that I can't compose just now. Those run about fifty-fifty whether they ever get it.
Depending on what you do for a living, you may frequently get emails that don't require an immediate response, but have to be retained just in case somebody brings up the subject again months later and you need to be able to go back and see what was originally said.
I'm a retired now, but a year ago I was a sysadmin and postmaster at a university engineering faculty. I received literally thousands of e-mail messages per day, each with at least enough potential to be important that I had at least to glance at it. For a postmaster, even spam is relevant because it needs to be examined to see how it got past the spam filters. Handling mail was a full time job, and still, at the end of each day, there were always a few dozen that managed to go unhandled. I shudder to think how it must be at Gmail, Yahoo, or Hotmail.
Back in the day, when my father went on vacation, "While You Were Out" phone messages would pile up on his desk. When he returned, he'd throw them away on the grounds that, if it was important, they'd call back.
Theophylact, I haven't worked for the government since before there was email. But employees at most companies are told that the IT department keeps copies of *everything*. It doesn't matter whether we delete it from our own inboxes.