A 4GL is a "fourth generation language"; they were going to reduce the need for icky programmers back in the 70s. SQL is the only real survivor, assuming you're willing to accept that it counts at all. "This will make programmers obsolete" is kind of a recurrent form of magic tech; see 4GLs, 5GLs, the likes of Microsoft Access, the early noughties craze for drag-and-drop programming, 'no-code', and so forth. Even _COBOL_ was kind of originally marketed this way.