There's a fourth part though, which is that certain parts of fandom "treat" me like a slasher, whether I think of myself that way or not.

Yeah, this. I'm not prolific enough to develop a reputation, I don't think. But depending on the fandom I have inadvertently 'passed' as an exclusive slasher, hetshipper, or gen writer.

And who my friends in that fandom are?

And this.