I'm no expert, but I have heard it said that
Kecak is NOT an ancient Balinese musical form but was actually
innovated in the early 1960's by an American musicologist
who, frustrated by the fact that the Balinese had no written notational system for their gamelan and other folkloric
rhythms convinced a group of balinese musicians to come up with an onomotopoetic system for singing the rhythms that he could remember.

I can't even tell you where I heard this, but I wondered if anyone is knowledgeable about the history of this amazing
musical/rhtyhmical form.

Anyone one enlighten us?

I do know that what we think of as Japanese Taiko drumming
is also not an ancient tradtion but was innovated by monks
in a monastery in the 20th century.

It just goes to show you that culture can be innovated.