Mate if you can parse it like that and remain unaffected then great, someone needs to do this job - and I personally wouldn't want it to be me. And I'm grateful to the people who do it. Even those who say it doesn't affect them.
But I don't think characterizing the people who are affected by these things as weak is helpful or fair. That is where I had an issue with what you said. Why do or say things to discourage empathy in the human population, or portray it as a negative attribute? I think it's a good trait and one that it would be nice to have more of in general not less, and in my mind the people who are affected by this are probably those with more empathy.
After all if these images were just pixels to everyone, and we could all just refuse to process them at a conscious level, then why is the job of removing them even necessary?