Paxman's whole shtick is that he argues with the people he interviews. Usually it is quite effective, because mostly he interviews politicians who are full of shit and he points it out in a way that more reverential interviewers don't. However, he probably doesn't mean everything he says: he just takes a contrarian view to whatever the interviewee says.
Quite right. I don't assume that Paxman has any of the opinions he appears to espouse, he's trying to get at the truth of the matter in a way that people unfamiliar with the topic can understand.
It's part of an interviewers job to ask the questions that the random person on the street would like answered. Sometimes an aggressive style is the best way to force the interviewee to get to the heart of the matter and make their best arguments (which is part of why lots of Colberts interviews are actually very good).
Perhaps it's cultural. I've noticed before that when Stephen Sackur interviews people from some cultures (including the USA) on HardTalk, and he asks them a difficult question, or confronts them with the opinions of their critics, they assume that he is personally attacking them. Interviewers are there to get the interviewees to talk and answer the questions that the viewers will have. It doesn't matter what their personal opinions are, and you shouldn't expect to be able to infer them based on the questions they ask.
My issue is that if you're going to play devil's advocate then you should come up with stronger arguments than "it doesn't mean anything". If there are legitimate questions about the program that isn't one of them
I don't think his job is just to argue against the theory; that remark - and the fact that the interviewee was unable to confidently rebuke it - shows that the people responsible for it are ill prepared, and that is a good argument against the practical implementation of the program.
I thought he was simply putting forward the comment that some people make - "what's all that gibberish on the screen?", and seeing what she has to say to that.
Symbols on a computer don't mean anything. They're only interesting for their manipulation of outputs that can be used as physical control systems, or in the values that we project onto them (the true content of endless font discussions that don't involve dyslexia or blindness.)
I'm comfortable with this, and it doesn't feel like a threat.