From the report:
"Grandmaster Flash, and I was prepared to dismiss his presentation
but to be honest I have to say that it was probably the best keynote
speech I have ever seen at an AES show. "
See what happens when we open up our minds?
But I fully understand your initial sentiment, and it's not
your fault - but certainly not the fault of people like Flash.
As a fan of the Golden Era of Rap, I enjoyed it immensely.