Some of Fox are/were actual reporters and tried their best to just report the news. The problem was with their opinion presenters like Hannity, Ingraham and particularly Dobbs and Carlson, they were the ones pushing Trumps agenda. Add in the likes of **** head Pirro, The Five and Fox and Friends who regularly entertained Trump rambling live via the phone and it is no surprise that the likes of Chris Wallace got drowned out on Fox.
However, back onto the subject, I'd hate to think that Southgate comes in for criticism from the hard of thinking over this because he's not only right to point out the booing, but he's also shown the strength of character to speak up and not just try and be politically impartial and keep his head down. I've always held him in high regard so I'm not surprised he's addressed the issue head on.