I still remember my university advanced Japanese class when our teacher asked us to pick a serious topic relating to Japanese politics, economics, or society. One creepy dude did a presentation on Japan's aging society (no problem with that), and inserted multiple pics of anime girls in bikinis a bunch of slides. So awkward.
Living in Japan now, I tend to avoid otaku. Just with any hobby, there is nothing wrong with enjoying something in moderation. Most of the English teachers obsessed with anime that I have met can't carry on conversation about anything else. It's weird, and frankly makes you a boring person if you let one hobby define you, IMO.