The notion of Stormzy headlining the Pyramid stage at Glastonbury is an intriguing one. On the one hand, an artist who’s only released one album being elevated to such a rarefied status – up there with Jay-Z, Paul McCartney, U2 and the Rolling Stones – seems unprecedented. On the other, a persistent rumour around the site suggests that Stormzy’s show cost more to stage than any other in the festival’s history. That may or may not represent one of the histrionic myths that annually circulates around Worthy Farm – festival-goers with long enough memories to remember Glastonbury before the arrival of the internet and its fact-checking powers may recall the story that used to go around in the 1990s that Cliff Richard had unexpectedly died. But watching Stormzy perform, you can believe it. His set opens with the kind of pyrotechnics most acts would use to triumphantly conclude their performance, and it doesn’t let up from that point on.

‘The greatest night of my life’ ... Stormzy. Photograph: Henry Nicholls/Reuters

You could argue that constitutes an attempt to bedazzle anyone who doesn’t think the 25-year-old rapper has enough material to fill a headlining set, but his performance passes without the kind of lulls you might expect from an artist without years and years of hits to draw on. Bulking things up by wheeling out a cover of Shanks and Bigfoot’s UK garage chart-topper Sweet Like Chocolate proves an inspired move, likewise performing his remix of Ed Sheeran’s Shape of You.

The sense of all stops being pulled out is hard to miss. If the first three songs pass with Stormzy on stage, with only his union jack vest, his DJ and an intense light show for company (the latter comes complete with a ticker tape that, instead of news events, shows the names of south London boroughs) that quickly changes. There’s a ballet interlude – designed to underline the fact that black ballet dancers now have shoes designed to match their skin tone – there’s a vast gospel choir, there are dancers, complete with a little kid busting moves, there are children on bikes popping wheelies as Stormzy performs Vossi Bop. There are also special guests: if Ed Sheeran can’t be here in person, then Chris Martin from Coldplay can, playing keyboards and harmonising on Blinded By Your Grace Pt 1.

‘For all the eye-popping, OTT aspects of the show, there’s something very human and touching at its centre.’ Photograph: Dave J Hogan/Getty Images

For all the eye-popping, OTT aspects of the show, there’s something very human and touching at its centre. When not imperiously rapping, Stormzy looks genuinely overwhelmed by the size of the crowd he’s drawn on what he describes as “the greatest night of my life”. Another guest, fellow rapper Dave, congratulates Stormzy at length on his achievements before leaving the stage, and, under the circumstances, it doesn’t feel like hyperbole. As Dave seems to suggest, Stormzy’s sheer charisma and talent have elevated an entire generation of black British music. Stormzy himself pays tribute to a string of new-school British rappers as varied as Little Simz, Not3s and Slowthai – and all of them would not be in such a strong position without Stormzy.

As he performs Shut Up, the track that turned him from an underground figure to a mainstream phenomenon, or stands centre-stage amid an explosion of confetti with arms outstretched before launching into Big for Your Boots, Stormzy’s performance doesn’t feel like a personal triumph so much as a victory lap for British rap: after decades as US rap’s poor relation, here it is, headlining the biggest music festival in the world in considerable style.