On the eve of its launch, Disney Plus — Disney’s online streaming service — aired trailers prominently featuring The Simpsons,” the groundbreaking cartoon and longest-running scripted prime-time series.

In one trailer, the Simpson family is happily attired in popular Disney character costumes — save for Bart, who enters half-dressed as Mickey Mouse and laments, “I won’t do it. I don’t care how much they pay.” Homer, garbed in ill-fitting Iron Man armor, threatens Bart, who capitulates by placing Mickey Mouse ears atop his signature spiked hair.

Homer orders the family to smile, and as a flashbulb goes off, Bart moons the camera but quickly is censored by the Disney Plus logo zooming in over his posterior. Bart’s sophomoric gesture is indicative not only of Bart’s incorrigible nature but also of his — and the series’ — depleted power as a counterculture icon. The longevity of “The Simpsons” has rendered its satire ineffective, for it has become — and perhaps always was fated to be — the very thing it once ridiculed so effectively.

Dec. 17 marks the 30th anniversary of “The Simpsons.” In 1989, the show was a bold and risky choice for the then-fledgling Fox network.

Fox had had modest success, most notably with the irreverent sitcom “Married With Children” (1987-1997) and the sketch comedy series “The Tracey Ullman Show” (1987-1990), on which “The Simpsons” began as a series of popular shorts. But the rest of its programming had failed to resonate at a time when television was dominated by NBC’s Thursday night comedy slate, which featured three of the four highest-rated series in prime time — “The Cosby Show” (1984-1992), “A Different World” (1987-1993) and “Cheers” (1982-1993).

Moreover, none of the Big Three networks (ABC, CBS, NBC) had aired a cartoon in prime time with any measurable success or longevity since ABC’s “Wait Till Your Father Gets Home” (1972-1974). NBC most recently had tried a cartoon, but “Jokebook” lasted a paltry three episodes in 1982. Factor in that “The Simpsons” was a parody of the family sitcoms then dominating the airwaves, and it becomes even more obvious how much of a gamble it was.

Timing was on the show’s side, however: The 1989-1990 television season saw “Roseanne” (1988-1997) narrowly defeat “The Cosby Show” in the ratings. With its working-class, occasionally crass protagonist and bickering family, “Roseanne”along with “Married With Children,” which was a modest hit — not only countered pristine, cheerful family sitcoms like “The Cosby Show” but also carved out a space for “The Simpsons.”

For more than a decade, the cartoon showcased uproarious, effective satire of virtually every aspect of American society. No target was safe — especially not the corporation that today owns it. The series frequently jabbed at Disney, often playfully but occasionally venomously.

For example, season six’s “‘Round Springfield” (1995) — often considered by critics to be one of the series’ best episodes — features a brief gag that took a sharp dig at Disney. The episode is centered on the death of Lisa’s musical mentor, Bleeding Gums Murphy. After an extensive search, Lisa spends the bulk of the episode trying to procure his only album and get it played on a local station as tribute.

Upon doing so, Murphy appears in the clouds to thank her. As a play on a similar scene in Disney’s “The Lion King (1994), Murphy is joined by “The Lion King’s” Mufasa, who states, “You must avenge my death, Kimba, I mean, Simba.” The line is a reference to “Kimba the White Lion” (1965-1966), a Japanese anime series with striking animated and thematic similarities to “The Lion King.” Today, thanks to online video, accusations of plagiarism regularly hound Disney, but “The Simpsons” was among the first to take Disney to task for flagrantly borrowing without attribution.

The inclusive nature of the show’s satire — no target was off limits — had the dual effect of making it popular among disparate groups while also centering it in national political discourse. Pointing to its willingness to make fun of both political parties, showrunners often positioned “The Simpsons” as politically neutral. But the show once engaged in a public feud with President George H.W. Bush, which resulted in Season 7′s “Two Bad Neighbors” (1996), in which Bush moves to Springfield and engages in a tete-a-tete with Homer and Bart. Bush’s laments about the show exemplified how frequently it nailed satire in its first decade, offering takes that were subversive and critical of authority — wherever that authority might lie.

“The Simpsons” sparked an adult cartoon renaissance. Shows like “Family Guy” (1999-present) and “South Park” (1997-present) owe a debt of gratitude to “The Simpsons” for their existences despite, at times, making “The Simpsons” seem less cutting-edge.

Therein lies one of the problems for “The Simpsons.” Having pushed boundaries, opened Americans’ minds and normalized a certain amount of bawdiness in televised cartoons, the show raised viewer expectations for cartoon satire. Subsequently, its own voice seemed tame in comparison to what it has made possible. Without the limitations of being on a broadcast network, “South Park,” for example, was able to address taboo subjects more fervently and overtly than “The Simpsons.” While “The Simpsons” had once seemed shocking — prompting Bush’s complaints in the show’s early days — albeit wrapped in what is essentially a traditional family sitcom, the cynicism of “South Park” and the absurdity of “Family Guy” stole that thunder.

Nonetheless, “The Simpsons” endured as one of the most popular shows on television, even if it was no longer at the cutting edge of satire. “The Simpsons Movie” (2007) reignited lagging interest in the series. Well received by critics and fans alike, the film was indicative of what the series has become in its latter years: mostly passable but occasionally hilarious and poignant.

Though the series is no longer ahead of the zeitgeist as it once was, every once in a while, it compels viewers to return in the hopes that they might catch those few “good” episodes. The release of the entire catalogue on Fox’s streaming service and a few full-series marathons also have drawn viewers back. That said, viewership numbers have plummeted precipitously from their peak. Season 30 featured the show’s lowest ratings, with its season finale drawing just over 1 million viewers. What was once a young upstart is now the status quo, seeking to remain relevant in a shifting media market.

Even worse, one of the show’s popular recurring characters has received well-warranted, overdue examination. In 2017, comedian Hari Kondabolu released “The Problem With Apu,” a television documentary that explored the impact “The Simpsons’ ” Indian convenience store owner Apu Nahasapeemapetilon has had on people of South Asian descent. Situating Apu into a history of brownface and blackface performance, Kondabolu highlights how Apu — voiced by white actor Hank Azaria — has been used not only as a means to insult South Asians but also as a means for typecasting them. In the past, the series either has ignored such controversy or co-opted it for self-aware critique.

However, in this instance, “The Simpsons” responded with an episode — “No Good Read Goes Unpunished” (2018) — in which the typically progressive Lisa laments a rise in political correctness as she glances forlornly at a picture of Apu. The woeful response is indicative of what appears to be the show’s final descent from trenchant satire to tone-deaf mediocrity and reflects a loss of the self-awareness that made the series great.

Season 10′s “When You Dish Upon a Star” (1998) featured a billboard that reads “Twentieth Century Fox-A Division of Walt Disney Co.” At the time, it was yet another chuckle-worthy sight gag about Disney’s growing empire shortly after its merger with ABC. “The Simpsons” was an important part of a nascent network’s push for legitimacy as the old-guard oligopolies consolidated power. However, as “The Simpsons” continued, Fox grew — largely in part because of the show’s popularity; as a result, its heckling of Disney’s ubiquity became less potent.

Humorist Molly Ivins once wrote that satire “has historically been the weapon of powerless people aimed at the powerful.” As a commercialized product delivered by a global corporation, “The Simpsons” never has been powerless; its subversiveness always has been relative. However, the series now is every bit the mainstream product it once pilloried, particularly as it stands at the nexus between two oligopolies, Fox and Disney. Its status does not necessarily mar its ability to elicit laughs — but it is a far cry from being the sharp, countercultural series it once was.