Modern Hollywood is ruled by franchises, and these days, there’s no bigger franchise than the Marvel cinematic universe. The release last week of “Avengers: Infinity War” marks the 19th film in the superhero series.

“Infinity War” is the culmination of 10 years (going back to “Iron Man”) of story lines and character arcs, a sprawling finale that is at times exhilarating and exhausting, overlong and underdeveloped, predictable yet also, in its final moments, genuinely shocking. It has been mocked for aspiring to be the most ambitious crossover event in movie history, and although no studio executive appears to have ever said those precise words, the label captures the grandiose spirit of Marvel’s project. It’s a $300 million superhero opera on a cosmic scale.

That an overstuffed picture like this holds together at all is impressive enough. Yet messy as it is, “Infinity War” actually works reasonably well. Which makes it a fitting quasi-conclusion to a franchise that has been defined not by excellence but by being consistently and reliably pretty good.

Marvel’s commitment to pretty good filmmaking has made it enormously successful and helped reshape the business of studio filmmaking. But it has also come at a cost — not only for superhero movies, but for ambitious studio filmmaking writ large.

“Infinity War” serves as a capstone to Marvel’s innovative filmmaking strategy — a rigorously honed blend of earnest nostalgia, winking self-referentiality, crossover narratives, appealing heroes and go-for-broke computer-generated spectacle.

Marvel adapted the idea of a shared fictional world, one in which, say, Captain America and Black Panther exist in the same timeline and might occasionally bump into each other, from its comic book source material, helping to bring the term “expanded universe” into our common cinematic lexicon.

The studio also applied a TV-like sensibility to blockbuster filmmaking, turning the superhero genre into a sort of workplace sitcom with aliens and explosions. Its biggest productions have been directed by the creator of “Buffy the Vampire” Joss Whedon and the brothers Anthony and Joe Russo, who previously directed episodes of “Arrested Development” and “Community.” The entire franchise is overseen by a single studio executive who essentially serves as a showrunner.

The studio’s core insight was that, with the right intellectual property, the centralized approach to storytelling of both television and comic books, in which each issue or episode is just a component in a long-running serial with an overarching sensibility, could also work for mass audiences on the big screen.

This strategy has produced a string of box office hits, an intensely loyal fan base, and even a surprising number of critical successes. It has also become the envy of Hollywood, with rival studios racing to create their own expanded universes, but often with mixed results (like last year’s abysmal “Justice League”). Other studios have cloned Marvel’s structural attributes — the pop-culture nostalgia, the serial storytelling, the knowing fan service — but none have managed to replicate the consistency of its product.

Consider Fox, which, somewhat confusingly, owns the rights to the X-Men and related Marvel superheroes. The X-Men films, which predate the Marvel universe, have varied far more in both quality and originality than their Marvel Studios counterparts: No Marvel movie has been as bad as the 2015 reboot of “Fantastic Four.” But no Marvel film has even attempted the elegiac despair of “Logan” or the manic, profane irreverence of “Deadpool,” and it’s hard to imagine that one ever will.

More than anything else, then, Marvel has succeeded because it has become a kind of quality guarantee, a brand that represents a workshopped and audience-friendly competence. Even the lesser entries among the Marvel-universe films are sturdy and watchable. No Marvel movie has a Rotten Tomatoes score of less than 66 percent; the top nine films have all scored 89 or better.

In an era where films routinely cost $200 million to produce and just as much to market, this is no small feat for a studio or its viewers. Marvel’s implicit promise is that you can buy a ticket for any of its films and know, with reasonable confidence, that even if the movie isn’t great, it is, at the very least, likely to be pretty good.

This quality guarantee has given Marvel the latitude to take big-budget risks that more conventional studios might balk at — and delivered equally large box office payoffs in return: It’s hard to imagine that a $230 million production of something as obscure as “Guardians of the Galaxy,” with a talking raccoon and living tree in its main cast, could have received a green light without Marvel’s presumption of an audience. And while various producers have attempted to develop a Black Panther film since at least the 1990s, it was Marvel that finally managed to transform it into a mega-budget cinematic reality — and Marvel’s best-reviewed movie.

Yet “Black Panther” also suggests the inherent limitations of Marvel’s model. The movie was directed by Ryan Coogler, a talented young filmmaker whose two previous films, “Creed” and “Fruitvale Station,” demonstrated a remarkable gift for emotional nuance and cinematic lyricism. That gift is still on display in “Black Panther,” but in a way that sometimes feels muted and constrained, hemmed in by the broad formulas and expectations of a $200 million superhero movie. Mr. Coogler stitched together a characteristically impressive single-take action scene in the middle of the film, but the climactic battle in Wakanda plays out with the same sort of pixelated weightlessness that is typical of Marvel movies.

To be clear, “Black Panther” is a better-than-average Marvel film. But it’s less a Ryan Coogler movie made under Marvel than a Marvel movie made by Ryan Coogler.

Given the current state of Hollywood blockbusters, one might be forgiven for assuming that a certain amount of poll-tested blandness is necessary in order to achieve mass appeal. But it’s not, even in the big-budget superhero genre, which in many ways was built on the idiosyncratic personal visions of pop-culture auteurs.

In the 1980s and early ’90s, Tim Burton’s “Batman” films were recognizably the products of their creator’s pop-goth freakiness; Christopher Nolan’s take on the character two decades later was similarly distinctive (as was “Dunkirk,” a good example of the opportunity cost of big-budget resources and talent getting focused heavily, if not nearly exclusively, on Marvel-caliber projects); Sam Raimi’s “Spider-Man” films clearly sprang from the same zany pulp obsessions that powered “Darkman” and the “Evil Dead” films. Notably, all of these films were box-office smashes.

Marvel hasn’t totally sanitized its films of directorial personality (the quippy banter of “The Avengers” felt notably Whedon-y), but it has done more to contain and constrain any auteurist impulses in order to maintain a more uniform tone, character, and quality level. But it has also made it difficult to make truly great pictures, the sort that only come about through a combination of luck, inspiration, experimentation and pop-art genius. And that, in turn, has made Hollywood less likely to pursue such projects as well.

The deeper problem is not so much Marvel as its imitators and boosters. As the major studios continue to chase the reliable returns of Marvel’s business model, and critics continue to celebrate Marvel’s merely satisfactory efforts as better than they really are, the likely outcome is that Hollywood studios will focus even more of their resources and top-tier talent on the production of movies that are watchable, even enjoyable, but aspire to little else. Smaller-budget films and television will fill in some of the gaps, as they already are, but the grandest productions will be reserved for the cautious and competent.

I have been a Marvel fan from the beginning; I don’t expect that to change. And there are worse fates, of course, than a world of adequate, risk-averse blockbusters, of solidly entertaining movies engineered for mass appeal. But there is also something depressing about a vision of the future in which a movie like “Avengers: Infinity War” represents the pinnacle of Hollywood craftsmanship and creative achievement. As superhero movies and blockbusters go, it’s pretty good. But I wish that the boldest ambitions of our pop culture overlords were a little more ambitious.

Peter Suderman (@petersuderman) is the managing editor of Reason.com.

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