When everyone talks with a megaphone, no one can hear anyone else.

I’m not sure whether he meant it this way, but Om Malik unwittingly hits the nail very much on the head:

“A few weeks ago, I told Jemima Kiss of The Guardian that Twitter was like a megaphone for everyone on the planet. And that’s what makes it so powerful.”

When everyone talks with a megaphone, no one can hear anyone else.