I don't know. I am reading this scene almost oppositely to you. I thought Siko was unbelievably unfair to lash out at Picard that way, considering he had years to think about it. Blaming Picard for that situation is no better than blaming a rape victim for the rape. Sisko is supposed to be intelligent not some brute who sends nasty letters to an actor who happens to play the bad guy in a TV series (as I've been told sometimes happens). If Picard had been as out of control as Sisko was in that scene he would have angrily told him that; instead of taking it as diplomatically as he did. Sisko's attitude might have been excusable days or even weeks after the events but not YEARS. How long does it take him to cool off and think a little about Picard's plight?
Fair questions.
But looking at all the inconsistencies given to Picard in "The Drumhead", especially in "First Contact: The Movie" where more years had passed but decided Picard shouldn't be there, etc, etc...
Oh, how many people who are being raped try to destroy an entire Federation? I would surmise that what Picard went through is much closer to cult indoctrination, with Locutus being the end result, admitting that most cults use more persuasive forms indoctrinating.
Oh, and as a survivor of a sexual assault myself - which is something I did not ask for, if you
really want to know what that feels like, I'll be more than happy to adumbrate one day - and even after decades the emotions are still raw - this is not atypical for many survivors of this sort of thing, so Sisko's reactions are not outlandish and, indeed, are somewhat relateable to me, especially if I ever had to deal with the (humans) who did what they did to me and what I've had to deal with... I'll leave it at that, for now.
And in a way, I was half-hoping Picard would talk about it, but he avoided the situation because he was still having emotions too. But that didn't help, did it?
We also have to count intentions in. Probably it wasn't Sisko's intention to kill anyone, just forcing the colonists off the planet. We don't know if exposure to that trilithium resin would have been immediately fatal, or that the colonists still would have had a couple of hours/days to pack their bags (but probably the sooner they were off the planet, the better).
Picard on the other hand was willing to let people die who didn't have a means of escaping that fate.
So what is worse? Initiating a lethal action that people have sufficient means to escape from (even if it means leaving their homes behind), or not initiating it, but still refusing any help to people who can't escape? I honestly don't know. And for me, legality (whether it is against starfleet orders or not, whether someone has sworn to uphold the prime directive or not) doesn't even enter into that equation at all.
^^this. Eddington's intentions were to kill, and Sisko had much bigger concerns.
What was worst was to let Eddington continue to go around poisoning planets and having "the needs of the many" be upended by the Cardassians ending the treaty and making a real mess. Sisko did pretty much everything else to stop an outright traitor, even saving lives that Eddington was willing to murder as a diversion. Sisko had little choice in the matter.