I think the reason why there isn't a mac pro with an i7-4790k like the new iMac with say a desktop gpu (NVIDIA maxwell or AMD tonga) is the same reason why there isn't a mac mini that most of us were hoping, which I think is the elusive mac mini w/ discrete gpu (iris pro, in the least) and a quadcore i7 cpu.
I don't understand that term people use called "cannibalizing." If a mac mini "cannibalizes" the iMac, then it's still an Apple profit, an Apple product, an Apple buy, an Apple win. But, I also kind of understand, if "cannibalizing" is true and is the norm for consumers to go for the mac mini, instead, of the pricier iMac that Apple will, indeed, feel the pinch in their pockets. But, aren't they already in the clear? A billion dollar company? Would they feel that pinch? I doubt it. And, they can sell more keyboards and mouse and Thunderbolt Displays because every mac mini buyer, even if they can't afford it, will want a Thunderbolt Display simply because it is gorgeous.
Or, if not a Thunderbolt Display, then Apple will drive sales of LCD's in general. Lol. But, I hope not because I really don't want people to buy "cheap" LCD's that are cheaply made. It makes well-made PC monitors like the Thunderbolt Display justify its price. And, my hope is that Apple will lower the price of their displays, while, maintaining the quality to around $500.... if, and when, this cannibalization occurs.
As to the mac pro with desktop CPU, instead of Xeons? The cannibalization for this mac pro should be non-existent, if you think about it. So, 80% of the people that buy mac pro's will buy the cheaper desktop version, instead of, the xeons? so, what? Again, billion or trillion dollar company. Will hardly feel that pinch.
But, I am afraid this isn't about what consumers want and to a lesser extent, market cannibalization that I tried to talk about above. The reason why (I think) apple doesn't make that "mac mini" or that "mac pro" is that Apple wants you to buy what they think you want. And, what you want is what Apple has in production. I don't know what the name for it is that would be "production." But, it is the parts Apple has to make their PC's. They have parts for their imacs and mac minis and portables that share components and then they have the xeon parts of the mac pro. The reason why this and that doesn't get made in a mac mini is simply the cannibalization that would occur in the production line, if the mac mini is selling well, let's say, would get priority. And, this mac mini is assembled in the part of the factory that doesn't need the fancy equipment or workers that Apple has invested in. So, it's Apple's "investments" that would be cannibalized if Apple builds the mac mini that 80-90% of us were hoping for.
Does this make sense, anyone? I should work for Apple and I need a job and I promise you guys that I will give you the mac mini you are all dreaming of, even if I have to re-evaluate and re-consider the entire Apple manufacturing factory assembly line.
So, in short, the "cannibalization" if we get the Apple computer we want is not so much to the market share profit (I don't know what the real term is). But, in the production space. Just imagine the Apple factory, if our dreams came true, where in one building, the production of this dream mac mini is rampant. Making and assembling a mac mini is less complex than a MBP or iMac so the machines and workers there are less complex. Not a lot of investment. Meanwhile, the factory building with the fancy machines and workers where the iMac is built is quiet and dusty. Maybe million dollar machines not doing anything because a cheaper product that doesn't need it is what we want. If, you guys, can picture this, I think, this is what the picture is as to why there isn't that dream mac mini we were hoping for.
Or, dream "mac pro" just to keep it relevant for this thread.....