Unless you think there is no difference between "write a statement on their commitment to diversity" and take some kind of pledge like Stalin or Mao. In which case you would be a total fucking moron.
That said, it is becoming very common for applicants to jobs to be asked to write a "diversity statement," along with the standard teaching statement and service statement. I don't like it - it is just fluff that no one cares about in the hiring process mandated by the university PC police forces.
So it is pointless, but it is not Stalin, no matter what your right-wing fucking moron websites tell you.