It's probably down to chance in some respects, but because my Shadowlands main picked Ardenweald, revisiting it and bargaining with the Winter Queen for the "release" of Ysera (whose seed (?) I discovered and protected during the Ardenweald campaign, I think) felt really tailored to me and my experiences, lol. So for me this was like "yeah, sweet payoff! Great setup!" but I guess if you did a different campaign in SL you'd be like "eh, sure".
When considering it in light of Blizzard's writing team trying to "fix" some of their mistakes from Shadowlands (or rather, the mistake that was Shadowlands) without simply pretending it didn't happen, I'd even say they managed to pan out some gold from that muddy river.
the ysera plot was part of the ardenweald story upfront, though the winter queen has extra dialogue if you're a member of the night fae when you petition for her trade. ardenweald ended up being one of the few really interesting and fleshed out concepts SL had so i do agree that it's good to at least revisit that well even if we could do without the rest
i'll give it credit for being a cool scene but the ysera payoff was largely just... ysera hanging around for no particular reason when the torch had already been passed to merithra during dragonflight's questing, and then going back after realizing she's not needed and accomplishing nothing.
but that's probably the best they could've realistically done given the circumstances and her scenes with merithra and alexstrazsa were sweet.
For how terrible Sylvanas's arc was set up I thought the ending and payoff was really well done. They've been killing it at closing arcs. Threading the needle for the Forsaken was a really high bar to clear but somehow they pulled it off. Easily my fave race in WoW and they managed to give them closure while also setting up their future. And now they're friends with Gilneas! I love it.
the forsaken payoff was... fine, but sylvanas's whole deal still rubs me the wrong way. it ended up being completely pointless and all in service to the same guy, even when different plot points were trying to make it seem like she was making her own decisions. arthas, her bargain with the valkyr, teldrassil... all of it was actually just the jailer pulling the strings the entire time, pitting sylvanas against herself and then taking all the credit. she's been robbed of any agency she ever had posthumously, which makes the idea of her needing some sort of punishment at the end even more comical... she wasn't even really
doing anything.
the main reason i'm fine with her just walking off into turbohell forever is that they clearly didn't know how to reconcile all the different plot beats and just made it all moot. there's just nothing for her to actually do since she never had a character at all now, just an extension of the jailer.