Which job? They are not CMs or Devs. They are arguably part of marketing and PR but that is an agreed on arrangement.
If you want to read the CM job description you can. I posted a recent one on the CC forum in a topic that had questions about the various roles of CMs, Mods, etc.
No, I don’t agree at all with the limited nature of Blizzard communications and never have. BUT, so far, CMs are not supposed to be entertainment personalities.
EDIT -