Because no one is withholding ARM cores. Intel wants to play in this arena but they can't get down to the low power levels required by phones.
My point is if it is a profitable and viable business opportunity, why is nobody competing in the space?
Do you think the people qualified to magically fill the void exist and will magnetically come together if for some reason Apple bought ARM and restricted distribution?
It takes a little bit more than a hole in the marketplace. I would say with them having such an overwhelming marketshare that the market exists. So if the pieces really did easily sit out there to compete someone would bring them together because with one major player with the overwhelming share of the market there is a lot of pie to take from them.
In other words, one person in a business in not much worse than none. There is still a ton of opportunity. Intel has billions to spend attacking this issue, and I am sure would love nothing more to dominate in the same area but can't.
People have this idea that if Apple pulled these resources off the table they would magically be replicated in no time. Cmaier's experiences with AMD tell you how important the people are in such developments, and thus there is zero guarantee that someone be able to readily fill the void with chips that are nearly as capable.
Sure someone would provide something, but the odds of it being as good any time soon would be very small, in my opinion. Or like I said, someone else would already be doing it.
If Intel evaporated tomorrow, would someone show up in the next 36 months magically capable of making better cpus? Not likely.
I am not saying it makes sense for Apple to buy ARM, or if they did to stop distribution to other companies. I am saying that if they did so, it would have a dramatic impact on those who require those components for mobile applications. For those people who competed with Apple directly, it would be the most severe, because they would likely be left with using vastly inferior counterparts for many years.