because "technical" encloses both "programming" and "design" (which by the way I don't think is as strategic as "Interaction Design") in the same way that "business" encloses "organization", "marketing" and "sales" (and possibly much more)
By "design" at Apple, they mean "how the product work" — I think Jonathan Ive is to credit for that sentence. And Jonathan Ive is an industrial designer: he's not just here to make things look cute, he's there to make sure a product works well and is enjoyable to use.
In a start-up, especially a software one, "how the product work" is responsibility of the developer(s).
He works out how it will look, how we will interact with it, how it will be presented, and why. [I'm generalising and condensing though