I will say that I do have thousands in my personal email... only in that I had it for close to a decade before I started deleting just about all new emails, if there weren't a few important emails that I hadn't archived outside email (license keys, etc) that I should, but maybe don't have outside email, I'd probably nuke it all.

For work, I'm pretty close to inbox zero... I'll mark unread if I need to followup and cannot at that moment, or if it's related to a yet-uncomplete task I'm waiting on from someone else. But at least once a week it's all empty.

I also tend to only check a couple times a day, and my personal email a couple times a week... similar no notifications. If it's important it will be IM, Text, or heaven forbid an actual voice phone call.