Bean counters are not running Apple. Every product goes through development that includes decision making on available technologies, new technologies, user experience, new benefits to user, fit within a category, creating a new category, production capability and hundreds of other points…including proposed cost and margin. To suggest that a “bean counter” at Apple is driving, let alone having a major impact on, new product development suggests you’ve really have zero idea of how product development happens at Apple or just about any company.
I’d also challenge this notion that there is a lucrative and untapped market for a touchscreen Mac/iPad converged product. Where are you getting your data from? I could just as easily argue that it’s far more likely that MacOS and the various Mac devices will become even more like iOS, including eliminating even more of the legacy computer operating things that some equate with being a “real” computer.