It's easy for us as an audience to say that Sisko was too harsh (I disagree, but whatever) ...but if a man who had suffered brain trauma and was not himself murdered your family, I'd bet real money you'd have an attitude when meeting him three years later after he was healed. If you say you'd be fine with him, I don't believe you.
That is an excellent point. You're absolutely right.
And if you were the family of the man who had brain trauma, you'd probably be upset with the guy hurting your family member because of a horrible act your family member had no control over.
Yes, we have the God's eye view, and can see both sides. And it is because we have that view we can feel angry with Sisko, sympathy for Picard, then happiness at Sisko finally working his way through his feeling and finally leaving the Battle of Wolf 359 behind him.
Some viewers can't.