The overloading of summary as the content warning. I think, and might even look into asking more people who work in the space of abuse about this. There's a suggestion at https://github.com/w3c/activitypub/issues/232#issuecomment-310132087 that I can see being defined in an alternative schema. I'd personally consider venturing down this route for the additional benefit of language resistance (not having to check if what r*pe is in French or Spanish to help with filtering) and can even be an onboarding option for clients.