Likely because Toole's text is about sound reproduction, not so much about sound enhancement. Toole applies if you apply. The home theatre and pop music enhancement guys are all over the internet. The art of sound enhancement doesn't get much treatment in Toole.Why wouldn’t Toole apply to rock or rap or pop?
Have you read Toole's 3rd edition? In total?
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I have considered respect for the musically inclined who produce pop and rock. I used to do it. The guys at the controls are creating that music just as surely as the singers and musicians. They are good at production and less considerate of reproduction.
So, be proud of enjoying the production value of pop and rock, not ashamed of it. But Toole is about reproduction. There's hardly a word there about adding sizzle, emphasizing the kick drum, or enhancing a snare. Or how to mic a Marshall, or which plug-in will make a singer sound like he/she is in your face. Or which speaker will up your dance rhythm.
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Just be aware of Toole's tome; you'll know if and when you want to know what he professes about reproduction. Because you will find yourself wanting to know, more than just wishing you knew.
To ~quote one guy here, "Toole is a science text, not Betty Crocker."