It's not that simple though, Cage's piece -- Silence 4'44" -- I don't think was tested, but taken as a whole I'd grant it copyright. It was art that caused reflection on the nature of a "work", it was designed to be "played" by a musician with any instrument, it was 273s long presumably to reflect on whether silence could ever be absolute. I suspect it was also intended to encourage the listener to observe ambient sounds as if they had meaning. That makes it distinct as a performance piece.
That logo is, within the field of logos, indistinct, boring if you will, if you sat down 100 logo designers I bet you'd get a few that look very like it. I'm not sure I entirely agree with it but having copyright but for a logo RTM is probably a stronger right anyway.
In short I don't think just being white noise is sufficient, but I don't think it excluded a piece of itself.