I loved the scene between Picard and Sisko. Was it fair? No. It wasn't fair to either one of them. Picard was both victim and victimizer and even after he's supposedly healed he has to look at people like Sisko who's worlds he destroyed. Sisko suffered a horrible loss, and it was Picard's face on the viewscreen that was telling him how futile all his efforts were and that he associated with his wife's death.
For Picard, it gave us a great opportunity to see him react to someone outside his tight social circle. The look on his face when Sisko angrily came out with Wolf 359 just said it all. Picard was pained both at the reminder of what he had done to him and had done to others along with the Sisko's loss. Sisko's own pain is understandable as well. If he was able to shrug off the tragic murder of his wife even years later, I'd be calling him cold and distant for that. Not for showing emotion and anger when confronted with his wife's killer.
Was it fair to either of them? Of course not. Picard knew Sisko had a right to be angry, even if placing the blame on him personally wasn't his fault. Picard blamed himself after all for not being strong enough to resist them so how can he hold Sisko at fault for being angry? Sisko deep down probably knew that Picard wasn't personally responsible, but sometimes emotion makes us do things we shouldn't. He probably came to terms with that once he realized his life was taking a new direction again after his second meeting with Picard. I personally liked the fact that they didn't need to say anything about it during their second meeting, as if they both understood.