Perhaps compare this to snail mail: if you recognize the piece of mail as coming from a known source of offensive material, you can choose to open it, discard i

Perhaps compare this to snail mail: if you recognize the piece of mail as coming from a known source of offensive material, you can choose to open it, discard it, or respond, as you see fit. This sort of filter just puts an envelope on material online so that choice can be restored/ported from earlier media behavior.