The Verge report that as well as being a jamboree of nostalgia-baiting obviousness, there's something not quite so hit-you-round-the-head going on in the video for Charli XCX's Troye Sivan collaboration 1999.
Namely: the shot of Charli as all five Spice Girls isn't your standard CGI creation — rather than being a composite of five separate Charlis dressed as each of the five Spice Girls, the shot's actually based on Charli and four dancers, and deepfake technology has been used to graft Charli's face on to the others.
It seems like using deepfake's AI-powered jiggery-pokery rather than more traditional CGI is partly to do with practicality and partly (large, we'd guess) to do with showing off. As the video's director Ryan Staake tells The Verge:
“When you start to think about the complexity of getting them in and out of wardrobe and makeup for each of those characters, it would take five times longer. So in a way, it was a pragmatic solution. But then, we also started playing off the bizarreness and aesthetics of it. It’s one of those things where part of the excitement is just trying to see if it works. Like, can we use this weird fake celeb porn tool in a legit music video?”
As you'll see from the Charli video the results are often a bit wonky looking, but that's an aesthetic that fits in quite well with where Charli's at sonically on a lot of her more recent mixtape work: sounds a bit wrong but wow technology, etc etc.