I've actually encountered people (in a fandom far, far away, nothing you've ever been involved in) who I know with certainty *purposely* didn't warn for all kinds of things for the LOLz (so disgusting to me, I can't even. I rarely get angry, but I'm *still* mad at those people. It was compounded by the fact that it was in a fandom where people had very visceral and personal emotional reactions to the story/characters, and often had very harrowing stories of their own in relation to the themes in the fandom).

And there are plenty of people who do the "I am an artiste/my fic is so important and different that warnings would ruin its artistry" thing -- I've seen that as well of course. And it's easy to think that way if you don't think it through, I suppose -- and I have to believe that even those people don't intend to cause harm -- of course they don't, since most people do mean well, I have to believe that. Generally, it seems like those are mainly newer/younger writers? I hope? (I have to admit I've never completely understood this pov, because to me, it's not the *facts* of a story that make it good or not; it's what the writer does with them, but, whatever).

So on a continuum, your maybe just not wanting to take the time/think it through is relatively benign (and I understand this -- even now, I'm thinking back to myself, oh whoa, should I go back and add a warning for x in story Z, and what about issue Y, should I warn for it?).

However, I fully get that not *meaning* to cause harm isn't enough in these areas -- I haven't meant to cause harm by some of the clueless things I've done, but they are still wtf-inducing in retrospect. So, yeah, I think you're doing it right -- not a martyr to self-absorbent angst *g*, but letting yourself feel that poster's pain, and that of others in her position.