My thinking as well, it’s very similar to how the first Apple Watch was rolled out: appointment for a “fitting” with a device that was eventually completely overhauled (so much as to call the v1 the “series 0” due to how different the v2 was). I think they want to see how users actually want to use this thing then rework the hardware to suit that.

Also, they want developers to figure out what they want to do with it. If it was a “development kit” people would still try to get their hands on one like with the Apple Silicon dev kit, but with this anyone can try it out if they have the money and time to do so.