When I played through the first three games the main story was presented in the quests. In Borderlands 1 Tannis’s Journal echo quests established the deeper lore, and carried the majority of the emotion. The main narrative was primarily mission logs that were very detached emotionally.
In Borderlands 2 the narrative was mostly in the main story, with echo missions providing character background as well, serving a very strong main story.
In the Presequel the narrative was the main focus and lost echos and echo missions were less relevant to the main story or served as character sketches.
Borderlands 3 took a major risk. We have a big quest narrative as the main game, with a number of lost echoes that provide character sketches and also key moments of plot development. Some of the brief arcs on these echoes are some of the best parts of the story, though they are relegated to being scavenger hunt items. Playing the echos alone, roughly 53 minutes of dialogue, showcases some great story telling and voice acting that is likely being skipped or heard out of sequence and context.
In addition to that, the Eridian Writings are a story unto themselves that is on par with Tannis’s echoes in Borderlands 1 in depth and emotion. And yet, they are offset by a game mechanic that only allows their play after completing 75% of the story they contribute to, and backtracking to every location after the fact.
There’s a feature film’s worth of story and character development that’s very well executed, but rendered skip-able or inaccessible, which unfortunately undermines the presentation of the overarching story.
Also, there’s a lot of dialogue between characters, and upon entering maps, that’s very significant when explaining actions and motivations, that will be skipped simply by entering an NPCs field of view, pressing “talk”, or choosing never to talk during non-mission interactions.
In a way it sets a speedy player up to have an experience that may be underwhelming if they forego all the additional narrative content.
That additional content has some of the best world building and story telling the series has had to date.