Damn, I dodged a bullet. My data was exposed, but looking through the transcripts of the exposed conversations, it just so happens not to include anything particularly sensitive. I'm a pretty heavy user of Notion and its agent, so I absolutely have had sensitive conversations in there in the past.

This is a really bad breach in the sense that an unlucky user could have very sensitive conversation content exposed in a way that could be attributable to them, if identifying information is in the messages. It could also expose sensitive information about 3rd parties, even if the user themselves was not exposed.