None of the other locations listed are particularly "iconic" about 5e, and to say each one is iconic even to a specific edition is a little bit of a stretch too honestly. When I think Ravenloft, first and foremost thing I think about is, you know, the castle? Where Strahd is? And since he's already shown up in promotional material so much I figured we'd run into him on his home turf, instead of maybe seeing him skulking around a cramped basement dungeon for levels 1-3. Heck, The Amber Temple would've made more sense since this adventure looks to have references to the dark powers, of which Vecna almost certainly was and actually might still be in some way.
You can argue it's iconic for Ravenloft, but I wouldn't, it's an incredibly recent "innovation" (emphasis on the "no") to the setting. And it's certainly not the only innovative thing 5e has done story-wise; I wholeheartedly think calling most of the 5e adventures disappointments is a touch narrow-minded. If your only concern is what they do or don't do that's entirely original and unique to them; Consider that the "lore" of D&D is, was, and always will be fluid, on top of the fact that every edition iterates on the ones before it by taking the good stuff and rolling it forward while leaving the old and undesirable tidbits in the past where they well belong. In terms of 1:1 recreations of things in 5e, the only things we've gotten that were just straight-up reprints was Tales from the Yawning Portal and, besides some details here and there, Ravenloft itself through Curse of Strahd. Every other book has looked to change things up, take an iconic dungeon and make something new with homages to the original inspiration, or just trudged into totally original tettitory from cover to cover.
