Let’s talk about political stances. It turns out you can just abstain from adopting a position. In doing so, you’re taking the meta-position that it’s not appropriate for you to take a position on a particular issue. In my humble opinion, it’s not appropriate for Derpibooru to adopt positions on issues that don’t arise from the show itself, the fandom and it’s culture, or the logistics of running the site. Which positions are adopted should be (and used to be) a compromise between the values expressed in the show, the values expressed by the fandom culture, and what Derpibooru can safely and legally host.
And I think Derpibooru basically had the right idea. Why are users allowed to post images supporting LGBTQ-etc? Because the fandom has been making characters gay and revering lesbians since since the beginning, so it’s consistent with the culture. Why aren’t users allowed to promote hateful ideologies? Because it’s a show about characters setting aside their differences and being nice to each other, so it’s inconsistent with the show’s message. So that covers images that adopt a specific stance. What about images that just depict things? What stance does Derpibooru adopt by allowing those?
Derpibooru values artistic freedom over morality and “good taste”. It adopts the stance that “So long as no one is harmed, do as you please”. It places a strong emphasis on personal responsibility when it comes to controlling what you do or don’t see. Thus, the decision to allow images tagged with “rape”, “foalcon”, “gore”, “torture”, “murder”, “nazi” and other things that everyone knows are bad, is not an endorsement of these things specifically, but an endorsement of artistic freedom in general. “Your right to say it”, etc.
Just a side point about Nazis. A person can have a fetish for “The Nazi Aesthetic”, without actually being a Nazi. In the same way, a person can engage with the subject matter in a work of fiction without actually agreeing with it.
This is the political stance Derpibooru should take. If they start compromising on their anti-censorship stance, there’s no telling where it stops.
“They banned that offensive thing instead of just telling people to filter it. Why aren’t you banning this offensive thing? You banned it because you disagree with it, doesn’t that imply you agree with the things you aren’t banning?”