As confirmed by the Harvard Business Review in an article about negotiation styles, this is the German national character.
Although I wouldn’t call my style confrontational, but direct and honest. With me, you will at least always know my sincere opinion. I won’t lie and I won’t do silly things like “trying to use non-verbal communication to convey signs” and let you guess (which is a woman thing anyway). If I want you to know something, I will tell you.
This saves everybody a lot of time, and it’s more reliable. There is no point in negotiating with less confrontational/direct people who will say “yes” or “maybe” to everything for fear of pissing you off, but then they won’t deliver.
On expressing emotions, I may be a bit different from the norm because I will easily get agitated if someone tries to bullshit me, and I will tell them straight away. But the “emotionally unexpressive” label is correct when it comes to talking about personal stuff. That doesn’t necessarily belong in negotiations, unless you already know each other. Don’t ask me “How are you?” unless you are prepared to listen to the story of my life. And don’t get sad if I don’t ask you. Either I am not interested or I don’t expect an honest answer anyway.