Some people would really like email to be as reliable as possible, even if that means they have to wade through a lot of spam.
By what twisted logic can a system where desired email is found when " they have to wade through a lot of spam"?
Have you ever inadvertently deleted a desired item in the middle of a delete-yes-delete-yes-delete-yes-delete-yes-delete-yes-delete-yes sequence that went on for "a lot of spam"?
How many times? Did you recover all of the desired items? How do you know that?
To me a reliable system is one that delivers what I want and only what I want every time. And having to pick the pepper out of the flysh*t is not my idea of "reliable".