The assertion that "CCPA requires companies to delete your data upon request" is not technically correct. What must be deleted is "personal information" and while I empathize with the notion that would include social media posts, I am not sure it actually does include them.

see: https://privacy.ca.gov/protect-your-personal-information/wha...

The closest thing mentioned is: "Contents of messages (e.g., emails, texts, chats)" but does that actually cover posts? I'm not sure and I can't find an authoritative answer that it does.