Because complex algorithms can reveal information that isn't immediately obvious from basic stats, let alone "gut feelings" that you get from merely watching a game. This type of thinking is what leads to disparities between who the best players actually are and who the fans think the best players are (see: baseball All-Star voting).
I wholeheartedly agree with you on the gut feeling vs. stats issue, but this complex algorithm in and of itself doesn't seem to reveal any information that isn't obvious from basic stats: Xavi is clearly seen as the "dynamo" from the basic stats perspective (in fact he routinely breaks passes received/made records). If one would come with a complex algorithm that would reveal something new (to me, to the media), that would be really exciting for me.
Since you seem to have an interest in such situations (complex techniques claiming discrepancy between consensus and actual performance), I'll go off on a tangent and shamelessly plug (again! don't people have any shame these days?) what I think is a very good example:
http://wagesofwins.com/wins-produced/how-to-calculate-wins-p...http://wagesofwins.com/faq/
I'm all for deep analysis of stats - for example, tracking which players are most often involved in the buildup to a goal or a chance, or determining which players are the best at receiving long passes. But this particular method doesn't seem to provide any fresh insight.
