The world view of the new atheist is, broadly speaking, positivist. They believe all knowledge is empirical, is determined through science, and any question without a scientific answer is a matter of opinion. They view philosophy, like religion, as a failed science, an attempt to get answers to empirical questions through non-scientific means. And thus they view philosophy, like religion, as deceptive. In their view religion deceives by telling people to have faith, to believe without evidence. And philosophy deceives through word wrangling, bamboozling people through empty verbiage. Neither is worth study, since both have been superseded by science.
The arrogance of the new atheist is the arrogance of a true believer. They believe they have the answers because they are arguing from science, and you are not.