There are fewer rock ‘n’ roll flameouts more fascinating than Oasis — the Britpop band behind blockbuster mid-’90s hits like “Live Forever,” “Wonderwall” and “Champagne Supernova” and led by the blustery, big-headed Gallagher brothers.

Liam was the front-man, a preeminent piss-taker for whom even stage presence became a put-on. A far cry from his freewheeling, tabloid-filling antics, Liam would strike an ironic choirboy pose in concert with hands clasped behind his back.

Five years Liam’s senior, Noel anchored Oasis’s otherwise ephemeral psychedelic rock with tunesmith soul and guitar virtuosity. The substance to Liam’s snappy style, Noel nevertheless secured a secondary singing spotlight of his own.

“Not a day goes by where I don’t wish I could rock a parka like that man,” Noel says of Liam in Oasis: Supersonic, Mat Whitecross’s new documentary about the band. “And I know he wished he could have my songwriting talent.”

That was the sibling rivalry underlying brash clashes and bad behavior that beset Oasis even at the peak of their popularity: Liam citing illness before an MTV Unplugged taping, then heckling Noel from the balcony while chugging beer and puffing smokes in 1996; Liam bailing on the stateside tour behind their most heavily promoted album yet, 1997’s Be Here Now; numerous arrests and accidents (including a vehicular mishap in Indianapolis) that plagued a 2002 tour.

It may seem surprising to learn that Oasis stuck it out until 2009, albeit like a wounded deer limping a long way before expiring. After last-straw slings from Liam, Noel bailed — a decision over which he would later express regret.

“What happened to us? That’s a big question that deserves a big answer,” Liam says at the beginning of Supersonic, which shares its name with a signature Oasis song and the speed of stardom at which the band ultimately flew too close to the sun.

There are, unfortunately, no big answers in “Supersonic,” a logy, synesthetic swirl of anecdotes and apocrypha that never generates the tension inherent to the best band-on-the-brink documentaries like Metallica: Some Kind of Monster. Instead, Supersonic is assembled exactly like Amy, 2015’s Oscar-winning Amy Winehouse documentary. (Its director, Asif Kapadia, serves as executive producer, along with the Gallaghers.) That means no talking heads, only voices atop reels and reels of archival footage.

The sheer amount of footage astonishes, but what felt piercing and powerful in Amy comes off here as slick hagiography — posturing in hopes someone would someday care about posterity. With so much footage, there must be video of that Unplugged heckling (and more malicious mudslinging), but we see none of it.

Whitecross never delves deep into the ways these brothers bent, and broke, under the weight of their massive egos. There’s more heartbreak expressed over their longtime soundman having to leave for audiological reasons.

The fleeting sense that Noel’s self-professed nonsensical lyrics afforded a creative escape from an abusive father — who never went after Liam the same way — is as psychological as Supersonic gets; a moment in which Noel talks down Liam, whose fists are ready, when they unexpectedly encounter their father in an Irish pub is easily the film’s high point. Also unremarked upon is Manchester’s storied music culture, to which the band offered a direct rebuke.

Whitecross settles mostly on a span from 1991 to 1996, pressing pause at film’s end on a pair of sold-out shows at Knebworth during which Oasis played to a quarter-million people. It’s as if Lin-Manuel Miranda ended Hamilton before the duel.

Liam and Noel nebulously kvetch about obstacles erected by “the industry” and half-heartedly lament disconnection in today’s digital world. The Gallaghers bemoan a lack of communal concerts like theirs at Knebworth, but you suspect they worry more that they were never again able to amass that many people.

Supersonic certainly has compelling moments, especially for fans — the earthbound ambition of early gigs, a revelation that the band was inadvertently on a crystal meth bender during its first U.S. show, a lovely Lost in Translation moment in which Noel escapes for a lost weekend with a San Francisco fan (and is inspired to write the understated, underappreciated ballad “Talk Tonight”).

But in the end, this documentary is too much champagne and not enough supernova.