Wind Waker easily. Zelda has been on a steady decline since then, both Handheld and home console releases. For what it's worth Skyward Sword I found to have at least a more consistent approach to design than TP does. TP doesn't know what it wants to be, but at least SS is very straightforward about wanting its overworld maps to be levels by themselves, more like dungeons or even a Mario game. TP has a first quarter where everything is all Twilight with rinse and repeat Tear Collection bullshit, then the twilight disappears from Hyrule the rest of the whole game and Wolf Link becomes a complete afterthought. Terrible game if the primary dungeons weren't so good.
I think creatively speaking BotW is another step down the slope of the Zelda decline. I think it's being pulled up again thanks to the entirely new approach, which is a breath of fresh air for the series (you're always so tempted to say that when it's called Breath of the Wild) but underneath that rapidly new approach is a continuation of the declining dungeon quality that started with Skyward, then ALBW and finally BotW.
I go back and forth on it I admit.
As for Wind Waker, I do think main dungeons were better in TP but that being said, the combat was also worse, and Wind Waker wins me over there. The main mechanics for the tools you use, including swordfighting simply feel slicker and helps the flow of the game inside of dungeons. The dungeon layouts are pretty diminishing return, borring way too many things that had become tropes since Ocarina of Time, but it's still very functional and fun to figure out. The story is amazing and it has the second-best side-content (minus all the fetch optional stuff like Korok sprouts) to Majora's Mask. It just had some really peculiar NPC moments that I still remember. There's a guy who wants to see a snapshot of the moon but doesn't wanna outright say it. There's a tower on Windfall that can be lit up by fire arrows. There's a rich family that becomes poor after the Forsaken Island kidnappings and their roles have become reversed upon return. A poor girl can be found in the streets but it's completely up to the player to bump into it.
In fact, a lot of the better things about BotW aren't exactly new, they were always within the DNA of earlier games, only, that level of systematization had never been so much at the forefront back in games like Wind Waker, but it is there. A scripted event isn't so scripted that the game will lock you into place and make you watch what it wants you to see. It's still up to you to discover all the additional storytelling there is to find, and it's all so wonderfully simple (as opposed to basic) and relatable that it sticks with you after it ends.
And lastly, that main quest is just fucking brilliantly written. This is Nintendo's best story of all time, ngl. The more you reflect on the story, and revisit the game, the whole conclusion the game leads to seems all the more inevitable. They take the exact same tropes as established by ALttP with the opening lore dump but perform it in a way that primes the story for its true thesis, which is critical look at the entire Zelda mythos and what it would actually mean to be born as a pre-destined hero. Ocarina of Time touched on similar notes, with Link being granted childhood as his reward for defeating the world's greatest threat, but in this game you're triumphantly being brought into the shoes of a former hero only for it to be revealed at the end that it's a selfish wants of adults imposing their world views on their successors. The reward is freedom from all that, and the crux of the whole thing is that it isn't only the proclaimed "Evil" villain who is to blame. It's actually also the person who wished to defeat it who refused to let go of their old and now irrelevant traditions.
Twilight Princess is about "EPICNESS" about being absorbed into a world of darkness, then you're free again, then Ganondorf is apparently back, and then the evil ruler who was thought to be the bad guy is actually just a weakling AND NOW GANON IS BACK, AND HE WANTS TO SIT ON THE THRONE AND LOOK EVIL... While nobody gives a fuck, apparently. But let's just beat him for old time's sake. Fucking, atrocious story. It doesn't even hold itself together by the ending. Oh and yeah, tragic mid-credits stinger that is completely unmotivated and nonsensical, here you go, THE FEELS.
Skyward Sword is more of a teeny story. It's sappy as hell, and it's also Naruto as hell, but it has its moments. I loved the rivalry with Ghirahim even though I wish he was a more substantial character. The story mostly holds up thanks to heavy emphasis on individual supporting characters like Groose, Zelda and Impa (Not Fi!), but the ultimate showdown with Demise is as Diabolus Ex Machina as it gets. (When an all-new bad guy abruptly steps in to be defeated at the 11th hour to force a resolution of the plot). The attempt at truly canonizing a timeline by telling this as an "origin" story fails because well... it's a fucking boring story, ultimately. Not nonsense like TP, but it also doesn't have an edge whatsoever.
And then they made ALBW where they take nothing serious and everything is facetious. Then they made BotW where the story is a complete afterthought. You go, Zelda. Now please make BotW2 the game it needs to be.