Those DJs are always down there
For years, there has always been a big following of techno and trance music. There were local DJs like Carlos Herrera who did some parties here and there and would mix it up with the occasional Hip-Hop record (after like 30 techno songs) and sell mixtapes but after the year 2000, the actual creators of the music started coming down and I think they realized how many fans they had when Carl Cox, arguably the creator of techno, went there and did a mega-party in the Capital, too large to have in any specific club so they did it in the street. Tiesto is just the latest one to catch on to that. I wish I would've been down there now to see how the clubs do it nowadays, it's been 4 years since I moved back.