Serious question, especially if there’s follow up reading. Where does that principle of assuming baseline good things about the other speaker in polite conversation come from?
Part of the reason that political discourse is currently so polarised and pushes us towards bad outcomes in our societies (thinking particularly of US and UK here, but I'm sure it applies elsewhere), like the recent riots in the UK, is that so much of it is bad faith, dishonest, assumes the worst of others, casually alienates to score points, etc.