Did you read the article? It's mostly about the business of running nightclubs and organising music events. Something that falls cleanly with the interest of the FT and its readers. The headline is just some SEO optimised clickbait to get traffic.
Plus, as I mentioned elsewhere. A non-trivial number of today's FT readers are the same people that were at those original raves in the early 90s.
I did read the article because I was interested in the decline of raves. I unfortunately found an article on something different. I'm willing to give them the benefit of the doubt and assume they wanted to draw traffic that would be interested in the article, and thus the mixup was an accident due to not understanding the difference between a nightclub and a rave, though that does call into severe question their knowledge on nightclubs. Alternatively it is possible they knew full well they were trying to get people who were not interested in nightclubs to click on their link, in which case they succeeded. Either way, my point stands.
Plus, as I mentioned elsewhere. A non-trivial number of today's FT readers are the same people that were at those original raves in the early 90s.