I don't know much about perfect pitch but I also don't see what's impressive about it. Perfect pitch is a party trick. "That's a Bb" is not a musical skill.
Is his perfect pitch in A440? What happens if the instruments are tuned to each other instead of a pitch? Is the music unlistenable because it's not falling into the right slots?
I didn't know a lot about it either until I delved a little deeper into several of Rick's videos on the subject. I believe he defines perfect pitch as the ability to identify a pitch accurately and every time without the aid of a reference note. (The latter ability would be called "relative pitch".) He firmly believes perfect pitch cannot be attained after the age of 6, and certainly not as an adult. However he believes that with work, relative pitch can be learned by the rest of us. As I understand him, relative pitch is being able to identify the relationship pitches and intervals in relation to others (reference notes). He considers this skill as just as important to the musician in the practical world. He demonstrates this also using himself at the keyboard as an example. He has personally developed this skill to an impressive level and you see it at work in many of his analysis videos.
I'm sure by now he has heard it all regarding the merits or drawbacks of having perfect pitch. I have seen it flatly stated here that it's a curse. I think that in order to address this, he has asked his son if he is bothered by out of tune instruments, and he claims he isn't. This may also be a learned behavior--the ability to live with it and still enjoy music that you perceive as out of tune, I don't know, just my own thought. He does a demo with his son where he pitch shifts some notes to fall just sharp or just flat to see how he reacts. Dylan describes it as a "mix" which nevertheless leans toward one side or the other. Sort of like how greenish-blue can lead more to the green or the blue side depending.
It's pretty interesting actually. It hints at lots of benefits in other areas and concepts of neuroscience that go way beyond me. I actually do think being able to identify Bb would be a valuable musical skill. Far beyond that, he recognizes the component pitches which make up chords. Imagine the deep understanding of music that would give a person, coupled with the training on piano and theory that the boy is also receiving from his father who is a music educator and musician himself. To see and conceptualize and internalize fluently and in real time like a language--just the way we understand and speak spontaneously and intuitively. That's the holy grail isn't it? I just look forward to seeing what he will be able to do with all of this in the future.