2 of the 4 examples of unacceptable behavior are responses to overzealous moderation. I can't see this helping with any of SO's real problems.
Every SO question I've asked for many years has required constant monitoring to correct people who don't actually read the question and either 1) try to answer a totally different, easier question or 2) try to get my question closed. It's exhausting and really makes me wish it had competition so I could abandon it entirely.
The first few items in their code of conduct should be:
1. Carefully read the question before you answer or comment.
2. Carefully read the question before you answer or comment.
3. Remember you're not helping the asker if you repeat answers he already tried or specifically anticipated and said aren't helpful in his question.