For Zelda fans, Tears of the Kingdom's final trailer was a huge deal because it demonstrated the extent of how different this game would be from Breath of the Wild. However, perhaps more subtly, it also hinted at another, even bigger departure from the rest of the Zelda series as a whole. That is a shift in the tone and theme of its story.
In almost all Zelda games, Breath of the Wild included, a central theme is ever-present that highlights the ability of one courageous individual to change the world. Link is on his own throughout his quest, and he fights against a world that has gone astray in order to restore it to its former glory. In Tears of the Kingdom's trailers, though, a shift is clearly present. Instead of the weight of the world being purely on one person, Hyrule's fate rests on the collective, and this fact is made apparent through both Princess Zelda's subtle dialogue and the imagery that accompanies it.
Zelda's Dialogue in the Trailers Indicates a Change in the Series
One of the first indications that Tears of the Kingdom is not going to be a run-of-the-mill Zelda story is in the second trailer, when Zelda states, "But Link, I am not sure you'll be able to stop him." Zelda's wavering faith in Link is profound considering how she ordinarily entrusts him with so much. Perhaps more importantly though, this latest version of Zelda goes through her own struggles with uncertainty and insecurity throughout both BOTW and Age of Calamity, but she's always admired the strength and resolve that Link shows. For this specific iteration of Zelda to waver in her belief of Link is very telling of how dire things have become.
Another important line from Princess Zelda comes at the end of the second trailer when she pleads to an unknown person, "Please, lend him your power." This again ties into the aforementioned theme of Link not being able to stop Ganondorf, with Zelda appealing to someone other than Link for help. This is one of the first indications that Link will need outside assistance due to the fact that he can't handle Hyrule's greatest threat on his own this time.
Things culminate in one of the Princess' most important statements in the final trailer: "But, you are not alone." This line appears to be a reference to the series' most iconic phrase: "It's dangerous to go alone! Take this." By remixing this classic sentence, Zelda is able to give a direct indication of just how different this game is tonally from the original. No longer is Link alone in this dark place with only his sword -- he now has the friends he's gained along the way to back him up, and he's going to need all the help he can get.
In past games, while the Sages, Fairy companions, and Zelda herself would lend their assistance, Link has always been mostly alone in his quests. Throughout TOTK's final trailer, though, Link is shown assisting a group of villagers in battle, fighting alongside Sidon, and standing with people of all races ready to fight by his side. These images serve to confirm that Zelda has been reflecting a clear change from a more lonely, individualistic journey for Link, to one that's more social, in which he must rely on the strength of others just as much as his own.
Tears of the Kingdom Is Focusing on the Best Aspect of BOTW's Mythos
In Breath of the Wild and its prequel, Age of Calamity, the storyline has never been presented as especially deep or thought-provoking. Instead, what carries the story forward and keeps the player engaged is the characters. The Champions, Zelda, and Link, all have lovable personalities that truly make fans interested in following their story and seeing how their individual character arcs pan out.
In this way, it's the group that makes players care, and it will ultimately be the group that supports and motivates Link to push through. However, while the Champions were important to Breath of the Wild, they were never entirely necessary to complete the quest, and Link found himself mostly alone in the wilderness. In Tears of the Kingdom, a move away from the solitude of Link to the collective of Hyrule and its Champions has been inferred by Zelda's dialogue and has now been seemingly confirmed in the imagery of the final trailer.
Ultimately, this move from the personal to the social is the right one considering how the best parts of the story in the Breath of the Wild continuity have been due to its cast of supporting characters. Even Link is able to show more personality than he has in previous games, thanks to his reactions to those around him. Link is rarely just the "strong, silent type" in any Zelda game despite his voiceless nature, but his innocent soul and sense of humor speak louder than ever here. Link is still Hyrule's last hope and the main character of the story, but it looks like he'll have to rely more on those around him this time if he has any hope of bringing down Ganondorf at full power.