That's definitely valuable, but not for a child in my opinion, it's the type of luxury equivalent to a Mercedes over a Renault. Perfectly defensible but, just like a Mercedes is hardly a starter car, I don't think an MBP is that fit for a starter PC. It's also mostly useless if you're not traveling for work regularly.
That said, does any of that even matter any more? People were learning Blender, programming and whatever else 15 years ago on low to mid range machines already. The equivalently priced - or dirt cheap second hand - machines of today are multiple times more capable at everything. Stick Linux and a $5 mouse in it and you're 90% of the way to a macbook pro in terms of user experience.
That's to say, I agree with the core of the article: kids will make the most out of the least. But I disagree that this particular laptop is a necessity or a boon for that. If anything, it's a hindrance for being a mac.