From TFA: "At that time Williams, on behalf of Twitter, acknowledged the confusion which likely would arise from the use of TWITTER in the marketplace, as well as instances of actual confusion which already had arisen."
It doesn't matter what "most people would agree" if the defendant themselves are on record acknowledging the problem.
I've never heard anyone confuse Apple (The computer company who sell music) with Apple (The record company founded by the beatles), yet you'd be a fool to not see the problem in the overlap when Apple were on contract saying they'd only use it in the computer industry and then started venturing into the music industry.