Interesting stuff. I think there is a form of bluntness, or ‘direct honesty’, that can come with being more open — openness requires more thought and awareness, especially if you’re putting yourself in a position where someone may question you. I find, personally, I can lapse into a brutal honesty because I like to be honest with myself — but it’s easy to forget that others aren’t so expecting or comfortable with that, or that they haven’t thought, or can’t think, about something that ‘seems obvious’. If I catch myself doing it, I’ll generally try to balance myself out, and just shut up and listen for a bit, or ask a ‘deliberately curious’ question that can help others to think things through for themselves.
That’s not to say I’m not obnoxious sometimes too — I’m sure there are times I’m really annoyed about something and the frustration seeps out into a conversation.
YMMV too, of course. That’s just what popped into my head when I read it ☺