Although I couldn't possibly know, I'd imagine that this was not so much a factual statement, it was more of a way of giving the documentary a narrative arc. Problems in each decade solved.
+3 for WH Lung. Camped near one of the guy's parents at latitude a few years ago and the dad put me on to a few of their tracks. Obviously went to see them play on a tiny little stage and they were absolutely brilliant. Already sound like a headline act.
Also noticeable that some of the acts that I've heard about but not seen before looked totally out of their comfort zone. Alfie Templeman could be great one day, but he looks very awkward on stage. The polished acts stood out a mile. I'm a Foals fan but was disappointed with them.