I disagree with this pretty heartily. I think the main takeaway from the reveal of Sylvanas' true allegiance or goal actually puts "Before the Storm" and "A Good War" into clearer focus. Mainly I think this because Sylvanas' strategy for the War of Thorns, and the beginnings of her proposed aggression with the Alliance, never made sense to me. The whole idea she sells Saurfang fang, the infliction of the "would" that would sap the Alliance of their morale and hope, was never a workable strategy. She gussied it up well, so well that she was able to gull Saurfang the rest of the Horde, but even from day one it was pretty obvious that it would be a failure to launch. Why would killing Malfurion and seizing Teldrassil stop the Alliance from working to avenge Malfurion and re-take Teldrassil? It didn't work in the First War when Blackhand took Stormwind, why would it work now? Then the burning of Teldrassil as its replacement "wound," why would this sap the Alliance of the will to fight? Saurfang calls her out on it immediately in "A Good War," and that was basically the moment that Sylvanas' motivations became clearer to me - it wasn't about the infliction of a wound, she just wanted war. Now we know *why* she just wanted war, she wants to feed Death and empower herself. It's a pretty linear evolution of her character through the gradual reveal of her goals ans aspirations. The only outlier here is Sylvanas' stated reticence about wanting to be Warchief, but that is easily explained away by the notion that she was reticent about it until she finally hit on a way to turn the situation to her advantage. That, in turn, feeds into "Before the Storm" and the requirement that she consolidate all power over the Horde for herself. It meant she needed a show of force to make everyone fall in line e.g. blackmailing Baine, killing the Desolate Council, and inciting an incident to stoke Alliance aggression to better facilitate her own casus belli.
This presupposes Sylvanas only has the one method of manipulating people. I also take Sylvanas' accusation about trust to Saurfang in a very different light - I think she thought Saurfang could be a kindred spirit to her much in the same way Nathanos was. He could be made to see the truth of her philosophy, as it were; as evidenced by how quickly and zealously her took to her plans for the war. He didn't betray her by forming a coalition against her, in this context (well he did, but that's not what she's talking about), he betrayed her by failing to be the sort of Orc she thought he was - he failed her by refusing her message, and holding on to what she considers a vain hope about the Horde itself. This is why she basically whispers it to him and him alone, as opposed from the context when she calls him a traitor out loud before the duel starts.