I didn't get a total feeling of maturity from his writing. Did you read it? Mostly low-ball shots taken at startup practices that are pretty commonplace now, primarily for their proven effectiveness. Like the fact that he was disturbed to find that Zack, being so young, wasn't an assistant but a manager. It's like the idea of promoting individuals based on results and performance, rather than age and tenure, was foreign to the author. And ironically, he displayed a lot of ageist qualities himself there. I wouldn't exactly characterize that as maturity.