Now, imagine for a second that you are a junior programmer, that only knows Java. You've heard of this thing called Clojure and you want to read and learn more about it. What would you think if someone called you brainwashed just because you only know Java ? For most people this means EOD (end of discussion). Calling someone brainwashed just because he doesn't have your level of expertise with other languages will just make it ignore the good parts of your comment.
In the end it is about what is more important to you: vent some steam about how much you hate Java or guide someone to learn more about a Lisp language.