They do poll a portion of the playerbase about games though from time to time. The first part of all these polls is that the person agrees to keep it to themselves and not share it. Inevitably they end up on wowhead or reddit.
You get an email with a link and you answer questions. It’s anonymous feedback. They usually revolve around some specifics in Retail or a Classic expansion for example. My last one was for another Blizzard game.