Huh? Email has that dynamic - You read one email at a time. Each email has to 'wait it's turn'. The only difference is the 'giving up' part: in voice, they decide to give up; in email, you decide it's a high noise mail and skip over it, 'giving up' for them.
If you're really getting that level of email chaff, cut it off at the source. Just throwing out half of it is the Wrong Thing To Do.