Legendary director Martin Scorsese ignited heated debate in 2019 when he compared the films of the Marvel Cinematic Universe to theme parks, expressing his view that they didn't count as true cinema. While "The Infinity Saga" had enough growth for many of its principal characters that audiences could reasonably defend them as cinema, Phase Four was a completely different beast -- one that largely proved Scorsese right.

Of course, Phase Four (2021-2022) also included such Disney+ series as WandaVision and The Falcon and the Winter Soldier, which did a solid job of further developing their star characters. But this isn't about television series; It's about the projects that grace the big screen: Thor: Love and Thunder, Doctor Strange in the Multiverse of Madness, Shang-Chi and the Legend of the Ten Rings and Eternals explored new ways to bring fantastical fight scenes to life, but at the cost of fully developing their superheroes.

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Thor: Love and Thunder and Shang-Chi Failed the MCU

Shang-Chi meets the Great Protector in the lake

Thor: Love and Thunder followed the titular Asgardian in the aftermath of Avengers: Endgame, which itself brought him some measure of closure after losing his mother, his father, his brother and presumably the love of his life. But instead of fully realizing the character and adding something meaningful to his arc, Love and Thunder seemed to completely undo the character development he experienced in preceding films. Thor needed to be a reckless warrior again without too much compassion because that way, the film could offer viewers explosive fight scenes and big jokes.

But it's not the only MCU film that does that. Shang-Chi and the Legend of the Ten Rings didn't undo any character development. It introduced a Chinese-American character and briefly explored his life as an Asian-American, only to shift the focus to a completely Chinese setting and culture, not to thoroughly explore it but primarily to use it as a gimmick for admittedly stunning fight scenes and magical creatures. There was very little emotional depth or any real exploration of Chinese-American or Chinese culture. The focus was on martial arts, giant dragons and ancient Chinese-styled settings.

The point here is that so many of these films were preceded in one way or another by a mountain of potential for a powerful cinematic experience. More often than not, however, it was cast aside for something far shallower than emotional depth. To be sure, that's no criticism of the VFX artists, cinematographers and editors who worked hard to create a memorable visual treat, but memorable is as far as it goes in Phase Four of the MCU. In that way, the MCU became every bit as exciting and fun as theme park rides and just as emotionally substantial.

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How Phases 4 and 5 Compare to Early MCU Phases

Doctor Strange and America Chavez breaking into cubes in Doctor Strange in the Multiverse of Madness.

It's worth taking a moment to compare the current phase to previous phases of the MCU and what it was able to accomplish with some of its major characters. Throughout nine films, from 2008's Iron Man to 2019's Avengers: Endgame, the MCU believably and subtly transformed Tony Stark from a selfish, warmongering billionaire into a true superhero who sacrificed himself to save the universe. It also transformed Captain America from an eager soldier blindly following orders into a warrior who had adapted to the world and trusted himself to do the right thing above authority figures.

What was perhaps the most remarkable facet of the franchise back then was that, as a shared universe, the MCU developed all of these characters and stories alongside its audience. There are younger audience members who might feel like they grew and changed with Iron Man, Captain America or Thor. And what's more is that the franchise made it clear that was what audiences could expect -- a grand, overarching story with ever-growing characters. Phase Four of the MCU made no such promise.

Even so, it's not something a filmmaker like Scorsese could say doesn't have a place in cinema, even if it's not preferred. Marvel Studios' approach to its laundry list of films is reminiscent of very early cinema -- what is referred to by film academics as the "Cinema of Attractions." For a very brief period in the early 20th century, filmmakers wanted to move on beyond recording real life on the screen, so they shifted focus to visual effects and animations and attempted to wow audiences with just that. The focus wasn't on any film's characters or any setting; it was on the spectacle -- the images alone.

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The Avengers prepared to fight at the Battle of New York

Those films too were very much, as Scorsese put it, like theme park rides. With so many new characters and no clear direction, it might be where the Marvel Cinematic Universe is headed outside of Disney+. It doesn't help that Phase Five kicked off Ant-Man and the Wasp: Quantumania in a less-than-stellar fashion. There are exceptions, of course. Spider-Man: No Way Home managed to accomplish a lot on top of bringing a close to Peter Parker's arc in the MCU. Arguably, so did Black Widow, and Black Panther: Wakanda Forever gracefully handled the titular hero's death by exploring grief and perseverance through times of uncertainty, but that's beside the point.

There are still plenty of discussions to be had about the place of big, loud comic book films in cinema. Being comparable to a theme park ride isn't necessarily such a terrible thing, and filmmakers have to admit that, during certain times, franchises like the MCU keep cinemas alive and kicking. The real problem, as Scorsese appeared to suggest, is that the sheer success of these franchises may ensure filmmaking resembles factory lines of colorful, formulaic products rather than artwork shaped by passion and insight into human experiences. The MCU still has a lot of potential, but it needs to get better at realizing it, or else Scorsese might be right that it can't be taken as seriously as some fans believe it can.