Once upon a time, “Game of Thrones” was the most hotly debated piece of fiction in the United States. In the two years since its puzzling finale, the series has suffered a precipitous fall from public memory. Yet nothing has quite replaced it as terrific fodder for arguments.

On the 10th anniversary of its debut, “Game of Thrones,” which took inspiration from the War of the Roses and aim at fantasy tropes such as dragons and noble knights, feels like the last true must-watch for grown-ups. The void the series left behind says a lot about the state of pop culture and its ability — or desire — to stir up real debates about big questions.

“Game of Thrones” was never for kids, and not just because of the copious number of naked sex workers who paraded across the screen, nor because of the show’s penchant for grotesque violence.

Rather, “Game of Thrones” was about questions that real adults struggle with, too. What is the most just and effective form of government? Can children of dreadful parents transcend their upbringings? How much deference do the survivors of trauma deserve, especially when they are determined to traumatize others in turn? What depictions of violence shock viewers into new revelations, and which turn suffering into mere pornography?

The series used a vast cast of characters to explore those questions and sent them on journeys that defied easy conclusions. To name only two examples, Daenerys Targaryen, played by Emilia Clarke, went from abused exiled princess, to liberator queen, to murderous tyrant. Sansa Stark, in a standout performance by Sophie Turner, began the series as a spoiled daughter of privilege and a collaborator with a regime that attacked her family, only to emerge as a wise, independent leader.

“Game of Thrones” didn’t always stick the landing, most notably in a finale that seemed to give up on the qualities that made the series so wonderful to debate. After eight seasons of exploring the flaws of every possible style of leadership, “Game of Thrones” declared “People love stories,” and that the person who knew the most of them should be king.

That’s the argument you’d make if you were advocating for a novelist-king, not telling a sophisticated story about power and human nature. It was a twist that reduced “Game of Thrones” to the sort of fantasy and fairy tale it had so ruthlessly dissected.

But the flaccid finale ended up being a warning of what was to come in pop culture and politics at large.

Since “Game of Thrones” began its run, other stories and franchises that share its dual ambitions to be both extremely popular and genuinely provocative have been few and far between. Jordan Peele’s horror movie about white liberalism, “Get Out,” is one such exception. Todd Phillips’s dark super-villain origin movie “Joker” might count as another, though it’s more an expression of nihilism than a coherent political argument.

Meanwhile, Disney’s Marvel Cinematic Universe has conquered the world through careful cultivation of the maximally profitable PG-13 rating. In pursuit of profit, Marvel has largely surrendered the ability to explore grown-up questions about sex and romance and prioritized a certain political neutrality. Characters barely date; their family lives, when they exist, are meant to signal personality traits, not drive exploration. All political conflicts are personalized; who are superheroes to be limited by deeper systems, after all?

“Black Panther,” the closest the franchise came to political provocation, poses a scenario with no real-world analogue: What if a wealthy and technologically sophisticated African nation had declined to help the Black diaspora? The answer is not exactly groundbreaking. Otherwise, it’s all compromises: Government regulation is good except when it interferes with a good man’s conscience. Surveillance technology is bad when bad people have it and awesome when the right people are in charge.

There is politically ambitious mass art for grown-ups out there, of course, but it would be impossible to call much of it popular, or even well-known. Damon Lindelof’s 2019 continuation of the grown-up superhero comics “Watchmen” was a tremendous exploration of the legacy of racial trauma in America — and it never pulled in a million live viewers per episode. Director Emerald Fennell’s acid revenge drama “Promising Young Woman,” a timely exploration of sexual violence and feminist vengeance, is nominated for an Academy Award for best picture — and a poll suggested that just 34 percent of “active entertainment consumers” had even heard of it.

Maybe this is a logical response to a consumer base that’s divided between wanting politics out of culture and making sure culture conforms to neat political positions.

But “Game of Thrones” became a hit in part because it took a third path. The show put important questions in a new and fantastical context and challenged the easy answers. Oh, and there were dragons. It’s a shame more storytellers, and more audiences, seem to have forgotten just how entertaining big ideas can be.

Read more: