The Avengers are the face of the Marvel Cinematic Universe, with their initial union being a watershed moment for the superhero movie genre. One mostly forgotten element of the first Avengers film, however, is the death of Agent Phil Coulson. The original character debuted along with Iron Man back in 2008, and he was a consistent part of other Marvel movies that followed.
Phil Coulson's death was the first event to bring the Avengers together, but this sacrifice has gone unacknowledged for quite some time in the MCU. In fact, the seminal superhero team seems to have completely forgotten the person who first brought them together.
How Coulson United the Avengers
The Avengers first came together in the appropriately-titled 2012 movie, The Avengers. The catalyst for their union began with the machinations of the mischievous Loki and his attempt to invade New York with the Chitauri. Just before the attack, Loki also killed S.H.I.E.L.D. Agent Phil Coulson, which was a huge turning point in the film.
Following Coulson's heroic death, Tony Stark told Loki that "If we can't protect the Earth, you can be damn sure we'll avenge it." This supposed vengeance appeared to refer to a potentially fallen Earth, but it also clearly stemmed from Coulson's death. From there, the Avengers Initiative became a reality, with the heroes banding together to avenge their fallen ally and wearing the title with pride. Unfortunately, not many of the Avengers characters were even close to Coulson, with Stark having the most on-screen interaction with him theretofore. Even then, they weren't exactly friends, making this honoring of Coulson's death somewhat out-of-left-field. Since then, however, the reasoning for the Avengers' initial team-up has become even more muddled.
Coulson's Forgotten Legacy
Since the first Avengers movie, no one in any of the films has so much as referenced Loki's murder of Coulson. The Avengers themselves are automatically renowned after the events of their first film, but Coulson and his death remain in obscurity. There've been no statues or other such emblems honoring him, despite how supposedly important he was to the heroes coming together for the first time. There's definitely nothing in the way of a press conference or similar event announcing that the Avengers were fighting in the memory of such a heroic, normal guy.
Likewise, no one in the films has acknowledged Coulson's resurrection in Agents of S.H.I.E.L.D., with Fury and Maria Hill being the only ones aware of it even happening. This could be argued as stemming from the one-way street that was the pre-Disney+ Marvel Television shows, which referenced the movies but were rarely, if ever, referenced in return. This is even more tragic, as Coulson's heroism in leading a new team of field agents behind the scenes and keeping threats from harming the MCU is rendered inconsequential in the grand scheme of things.
This makes it almost seem like Coulson's unfortunate death was just a tool used by Fury to unite the Avengers and nothing else. If he had been any other random S.H.I.E.L.D. agent, nothing else would've really changed. The worst part about all of this is that Coulson was one of several successful media-first characters, appearing in Marvel's movies before being adapted into the comic books. Sadly, the medium of his origin has forgotten him, and it's almost as if he never existed in the MCU.