From IGN: “Borderlands 3 has prepared an update that theoretically enables full crossplay across all platforms but developer Gearbox has been told to remove crossplay support for PS4 and PS5.
Gearbox CEO Randy Pitchford tweeted today explaining that there was good and bad news for Borderlands 3 players, and explaining that “the publisher” had required the removal of PlayStation platforms from crossplay support.”
Source: N4G PC Borderlands 3 Was Ready to Allow Full Crossplay, But PlayStation Support Has Been Pulled