It's a response to a pretty unfair characterization of people who recognize themselves as victims. The reason some are irritated with people who claim to be victims is because of their activity and action, not because of their wallowing and passivity. When people are wallowing in victimhood rather than speaking up about it, the people who have a problem with that are the compassionate, not the comfortable and resentful. Wallowing in victimhood is depression.
Stoicism does not advocate for passivity at all. Just look at Marcus Aurelius, one of Rome’s greatest emperors.