In the past, the MCU has tried to claim that it’s all about family, particularly with the Avengers. In Endgame especially, there was a focus on how these characters supposedly see each other as family, because a lot of them are estranged from their own biological family (or their real family is dead). However, this always falls flat because the audience is never really shown why the Avengers are a family, they’re just told about it. The moments that are actually seen on screen are just of the Avengers constantly fighting, to the point where they have the relationship of coworkers, but nothing more than that.
The MCU was more successful in its approach towards a found family story with the Guardians of the Galaxy movies, but they have had fewer on-screen appearances than the Avengers. However, it finally seems like Marvel has managed to nail the found family dynamic with its newest entry: Eternals. The characters that this film centers around are much more believable as an actual family than the Avengers ever were, and director Chloé Zhao managed to get this feeling across in just one movie (as opposed to the 11 years Marvel had with the original Avengers characters). How did the team behind the movie manage to do this, and what exactly is it about the relationship that the Eternals have with each other that works so well in the story?
One of the main reasons that the Eternals work so well as a family is that the movie shows how they're willing to make sacrifices for each other and that they're willing to protect each other no matter what. Gilgamesh and Thena are a perfect example of this, as he offers to stay with her and help her through the struggle she faces with Mahd Wy'ry. Their relationship is very sweet and it's clear how much they care about each other. It's so warm and lovely in comparison to anything the Avengers have ever done for each other because they literally split up whenever they get the chance. The Avengers rarely seem to be together unless it's for a team-up movie, and it doesn't seem like any of them would give up their initial plan for their life to live remotely and care for another member of the team.
Of course, that specific situation is extreme, and that alone doesn't prove that they are a terrible model for a family, but it's just interesting to compare how much closer the Eternals are with each other, and how that caring dynamic is so much more evident even if they've had a lot less screen time. When they all come together again after years apart, they speak to each other as if barely any time has passed at all, and they don't seem awkward or uncomfortable around each other. These are clearly people who have spent centuries together, and have such a deep bond that such a (comparatively) short time apart can't break.
The time frame is obviously one of the more important factors in what makes them a closer family than the Avengers, because while the Avengers had less than ten years to be a team, the Eternals have been together throughout all of the ages of human history on Earth. Because the audience is aware of this and sees them together throughout various points in history, it makes it so much easier to believe the close family dynamic within such a short time of getting to know them on screen. It also helps that the actors all have such good chemistry with each other, you instantly believe that they care about each other as much as they do. However, the Avengers movies should have been able to achieve a similar dynamic with so many more movies, and yet the viewer still rarely gets the sense that the members of the Avengers actually like each other.
A central conflict to so many Avengers movies is that the team can't get along. It's a main point of their initial team up in The Avengers, and it never stops after that. In Avengers: Age of Ultron, they argue about Tony's creation of Ultron. The whole plot of Captain Ameria: Civil War (a pseudo-Avengers movie) is that the Avengers are fighting, this time with some massive repercussions for the future of the team. In Infinity War, they're split up for half of the run time and the Civil War conflict is ongoing. Endgame attempts to remind the audience that these characters see each other as family, but it opens with yet another argument between Cap and Tony.
Families have conflict and argue, of course, but it feels like the Avengers never get a break from the drama within the team. The central conflict of Eternals is about this team and their family dynamic (and the subsequent betrayal they feel when that familial bond is broken), but the movie ends with the conflict, and spends the first two acts showing the audience how close the characters are and how much they love each other. When the conflict ends, it seems like it ends for good. Any future Eternals entries likely won't be full of storylines about how much certain members of the team hate each other, because they spent time establishing the bond between the remaining members in this film.
The main focus of the storyline of Eternals was why this familial relationship is important, and the story itself is truly about family. The "family" dynamic between the Avengers always felt like an afterthought in their movies, sort of like a side plot to the main point of the story. It always just felt like Marvel was trying to just tell the audience that the Avengers were a family rather than actually show it through their actions. Seeing the dynamic that the Eternals had was so refreshing, and it would be great to see more storylines like this in the future of the MCU. Eternals and Guardians of the Galaxy are proof that Marvel can tell a good story about found family if they dedicate the right amount of time and care to it, and it would make their characters and stories so much more sympathetic if they managed to do this more often.