I really wish I could find a better source to link to for this. By default, all free and paid customers are being opted-in to their data being used for AI training.

All your Confluence pages, Jira tickets, etc.

https://support.atlassian.com/security-and-access-policies/d... describes how to disable this, but it also appears that the setting to disable this doesn't exist (it's not visible on any of our instances).