I'm religiously agnostic, and I'm in the habit of trying to understand these conflicts from both an atheistic and Christian perspective. Based on that, your recognition that this issue somewhat breaks down along worldview lines makes sense to me.

[Disclaimer: The following is a description of my current thoughts on the topic. I could very well be wrong, but I thought sharing them might make for an interesting discussion.]

That said, I have an anti-PC view on this topic that AFAICT is somewhat a-religious. My perception (i.e., I very well may be wrong) has been that the pro-PC arguments I've heard contain some logical inconsistencies that I've been unable to resolve. And that some organizations with pro-PC policies use ad baculum or ad hominem attacks to avoid serious debate about their position's weaknesses. I think it's obnoxious to force others to obey their moralizing while refusing to submit their views to serious debate.