Tablets and smartphones are designed at every level to be devices for consuming (or being consumed by?) content. And if you do want to create things, they are terrible tools for that.
But yeah, my kid will not have a smartphone/tablet until they are at least 12. It's going to be pen and paper first, then a potato computer (gotta be Linux, they can try installing Wine to play games I guess)
I have a favorite comparison between learning how to use technical devices and learning how to use woodworking tools. You have to start out with the hammer, the chisel, the handsaw for small things first. And then learn to use the lathe, the drill, the bandsaw. Jumping straight to the big tool give you the big risk of losing a few fingers.
Also - why the pre-determined sequence of tech tools for your kid? I have found a much more valuable approach in general to tool selection is to first identify a problem or project, and then apply the appropriate tools. Learning tech for tech's sake to me indicates that we have become ensnared by our own tools and devices.
Edit: I will take your point though, that Apple at least attempts to produce premium products with a purpose. However, judging by the number of iPads and iPhones I see being used as passive content consumption interfaces, I'm not sure the outcome is much different.
I did my last leg of high school on an school-mandated iPad, and it's not hard to get what everyone here is talking about. Want to do CAD? Gotta get a different machine. Want to record music? iPads don't have the drivers for our DAC. Want to type an essay? Go rent a detachable keyboard from the library. So on and so forth until you never feel motivated to create anything superfluous again. It was an exceptionally poor replacement for a laptop, particularly when I wanted to make something or do creative work.