Is there a word or concise English expression for the kind of discussion that is heated, perhaps a bit contentious or pretentious, but ultimately off-topic, vague, or too abstract to be useful?
A word-picture that comes to mind are a bunch of stuffy politicians or inexperienced young professionals arguing for argument's sake, to display their knowledge or make their voice heard yet without contributing any value to the discussion at large, or worse, derailing it entirely.
Best Answer
I think the usual way of portraying this is with the phrase 'hot air'; they're not so much talking about anything important as they are just breathing at each other. Example:
Equal meaning can be derived from the terms idle talk, gas or wind, tall talk or inanity.
Of course those are nouns for describing the actual tone of the dialogue - if you want verbs describing their behaviour you could use babbling, yakking, prattling, ranting; it's all interchangeable really. My favourite for this kind of dialogue would probably be 'blathering', since it gives me the image of some old chap constantly talking without knowing what he's saying.
Hope that helps!