He wasn't actually questioning the value of reading. That question was only a rhetorical device that led into his main point. It was put there as a straw man to

He wasn't actually questioning the value of reading. That question was only a rhetorical device that led into his main point. It was put there as a straw man to start the process of disproving that there's no value to reading if you don't remember details. And that it's unnecessary to lament not remembering details.