I caught Jay Z and Kanye West's Watch the Throne tour a couple of summers ago; the spectacle was undeniably impressive, and the setlist a sharp reminder of just how many hits the two have had between them. The one part of the show that sticks in my mind, though, was the encore. They opened it with 'No Church in the Wild', but before the ominous bass of the intro kicked in, the pair turned their backs to the crowd and looked up at the enormous LED screen behind them. What appeared to be a pretty random compilation of images followed; some displaying war-torn cities, others impoverished villages, but the point of the exercise was presumably that we were taking a moment to think about those less fortunate than ourselves. Louis Armstrong's 'What a Wonderful World' played over the slideshow, because nobody's ever thought of that before. Ten minutes later, the duo would play 'Niggas in Paris' - by some distance the most gratuitously materialistic radio hit in recent history - no fewer than five times.

Just in case I thought that Jay Z's appetite for trite tokenism and glaring hypocrisy only extended to his concerts, though, Made in America is here to point out that I'd be sorely mistaken. This Ron Howard-directed documentary follows Jay Z's inaugural Made in America music festival, which took place over two days in Philadelphia in September of 2012. We kick off with some typically overblown self-aggrandisement from the Jiggaman, with his rags-to-riches story presented as the 'modern American Dream'. If you think that sounds tired, though, wait until you hear his reasoning behind starting up his own festival; now that there's a black president, he offers, the time's ripe for him to curate an event that brings the people together, irrespective of their race, gender or sexual orientation. In other words, exactly what music festivals have been doing the world over since Woodstock, and most of them without an act as brazenly misogynistic and homophobic as Odd Future on the bill; they make an unwelcome - but mercifully brief - appearance later on.

Over the course of ninety minutes, we alternate between live footage and interviews with most of the acts involved, Jay Z included. The vast majority of them present, with an unerring insincerity, the same clichéd dribble about believing in yourself and the power of dreams. Only Janelle Monáe seems to honestly buy into what she's saying, and her childhood stories of entering talent shows to try to keep a roof over her family's head are genuinely moving - particularly her comparison of her impossibly sharp stage attire to her parent's work uniforms. There's a nice performance of 'Tightrope', to boot, but musical highlights are few and far between.

Put simply, the lineup is weak, but that doesn't stop Jay Z constantly claiming that it's actually incredibly diverse; he waxes lyrical about how wonderful it is that the audience are willing to accept a bill that is largely dominated by hip-hop and pop and throws in a few thumpingly-uninspiring rock bands for appearance's sake (Passion Pit, The Hives and, most egregiously, Pearl Jam). Major music festivals have been routinely turning out programmes infinitely more eclectic than this for some years now, yet we're still subjected to such luminaries as Skrillex and the singer from Miike Snow alleging that Made in America represented some kind of radical collision of previously-incompatible worlds.

We also check in with some of the people working the less glamorous side of the festival; there's a food vendor who plans to use the money she earns over the weekend to refurbish her van, although the last time we see her, she's informing us in disconcertingly chirpy fashion that she's just lost a thousand dollars. A roadie who pops up throughout seems to be one of the only participants to have a proper grip on reality; about halfway through the film, he provides a intelligent critique of America's materialistic society, lamenting the difficulty of staying afloat without a living wage in a consumerist economy.

The idea that the festival, through its generation of jobs, is helping to provide some regeneration to a city ravaged by the financial crisis is vaguely hinted at throughout, but a solid narrative is ultimately never established. This is mainly because for every minute that Howard gives to the everyman, he hands two to the likes of Eddie Vedder, who's political views are almost as knackered as his voice, or to self-obsessed airheads like Rita Ora (in a bizarre segment late on, we cut away to London to afford Ora a five-minute ego trip that appears intended to serve as an advertisement for her new album). You wonder how Jay Z, who executive produced the documentary, could sit through the roadie's interviews without squirming; it's easy to spout nonsense about the potency of the American Dream when you're part of the one percent.

What potential there is for some interesting musical scenes is largely wasted. The two major coups for the organisers were the bookings of Run-D.M.C., for their first live appearance since the death of Jam Master Jay, and the enigmatic D'Angelo, who's delivered sporadic, rapturously-received returns to the stage whilst he continues to make Chinese Democracy look rushed with his work on James River. The interviews with Rev Run and D.M.C. are great, but all we see of their show are quick snippets of 'It's Tricky' and 'Walk This Way'. I'd advise you don't blink when D'Angelo turns up, either, in case you miss the thirty seconds of his set that made the cut, as well as a brief interview in which he tells us that he "doesn't compromise for his art"; given that he's spent fourteen years working on his next record, that is beyond understatement.

The only real credit that Jay Z comes out of Made in America with is that it's the first time in years that I've seen either him or Beyoncé on my screen without them trying to sell me something. It's a film that's every bit as humdrum as the festival it chronicles, with a feeble political narrative that veers between insipid and offensive. There are so many great music documentaries out there, and most of them don't involve a guy who named the lead single from his last album after a high fashion house pretending he's a man of the people.