Many of the historic figures who rose up to fight Sauron as he first began coming into power during Middle Earth's Second Age are spotlighted in The Rings of Power. The death of Galadriel's brother pushed her to pick up a sword and embark on an adventure that will bring her face to face with Dwarven Prince Durin IV.
The trailer emphasizes how all of the different groups in Middle Earth can sense that something is not right in the world and that the time has come for them to do something about it.
While the trailer does a good job of conveying the grand sense of scale The Rings of Power's going for, it's also a reminder of how dense and intricate narratives set in this world tend to be.