Now that just about everyone on Earth has some kind of presence on the Internet, it's only natural that people would create circles, communities, and "fandoms" around their interests and lifestyles just like they do in real life. However, as with any congregation of people, there will inevitably be some flaws in any given community because people themselves are, of course, flawed. While this may sound accusatory or otherwise unfortunate, it's actually a bit of a blessing so long as one is willing to admit to and actively address those flaws. Unfortunately, too many people refuse to see the issues within their chosen communities and therefore do nothing to improve them.
If you aren't familiar, there's a very large community surrounding metal music (of which I was once a part) with some extremely... passionate members. Having been part of said community, I usually feel pretty confident criticizing the issues I still see coming from it. In recent years especially, the metal community has had an ever-growing White Power movement that most fans willingly ignore under the premise of "separating the art from the artist". Not only that, but I've heard dozens of horror stories about the sexist and borderline misogynistic treatment of women at concerts and online. Lastly, this community also seems to have more infighting, name-calling, and judgment than any other I've been a part of (which says a lot, all things considered). These things are made more glaring by the fact that the metal community actively prides and advertises itself on being all-inclusive, spreading and selling a message of "brotherhood" across the board.
When I pointed these issues out on a friend's Facebook post the other day, however, someone met me with some pretty heavy resistance. While at first, I thought he was misunderstanding my point, I quickly realized that he was ready to push back against every criticism I had, eventually leading to him saying things along the lines of "Well, I've never experienced it!" It goes without saying that this is the exact wrong way to go about criticism to the communities you're part of. Especially when my criticisms weren't just simple opinions, but rather something pretty undeniable.
As someone who would now consider themselves part of both the gaming and comic/superhero community, I'm always more than willing to admit their issues with bias, infighting, and falsely-advertised inclusiveness. Because I'm aware of these issues, I actively try to avoid contributing to them myself (although I'll freely admit that I struggle to hide my biases a little too often). Therein lies the best way to approach criticisms of your communities. Very rarely is anyone being attacked an individual, but it is up to the individual to try and do their part to make necessary changes.