given it's Intel platform those same drivers would work on any "computer".
....
Why oh why oh why doesn't Apple just release OSX Open Platform??
The basic premise here is fundamentally flawed. Drivers in general are a low level interface between the hardware and the operating system. While the hardware may be the same the OS X kernel is
not the Windows kernel.
Given that you still have the pragmatically proprietary OS X kernel ( because the many of the drivers may have to interact with some small, but significant, pragmatic aspects in the OS X layers outside of the open source Mach kernel), it isn't an Open platform. It is an OS X platform.
Apple can easily produce a win/win with the driver developers by growing the Mac market. 10M mac users is a better platform to get return on investment (ROI). 15M even better. 50M even better. It is just as much about selling product for them as it is for Apple.
The hand waving part comes in with taking a left turn into the swamp with the implicit "... multiple PC clone vendors could sell more "Mac" platforms ... " . Perhaps, but what you have completely lost any creditable explanation for is where the win in it is for Apple. If Apple charges a high (or higher than for Apple label) then the clone vendors are at a cost disadvantage and won't substantively step in. If left the vendors shave costs to undercut Apple pricing then Apple sells less system sales. For Apple is about system (software + hardware) sales, not one of those halves.
The only hand waving scenario where it pays off for Apple is where Apple and Microsoft trade places. Apple has 80-90% of classic form factor PC market and Microsoft has 10-20%. Apple is no way going to bet the farm on that happening. Even they don't drink that much Cupertino kool-aid. The classic PC OS war is over. Apple's highest likely method to achieve max profits from the approximately 10% of the market they are constrained to is to cover that themselves. Not dilute it with several other vendors.
There is no "win/win" here. It is primarily about Apple takes less money so we can more products to choose from. It is just spin as "win/win".
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Apple is a hardware company first. OS X exists to sell Macs, not the other way around.
No, Apple is a systems company. OS X and the hardware coexist together so Apple can sell the combination.
There are more opportunities to do value-add it make unique additions to both "halves" of the holistic system than in purely trying to differentiate in either half.
If Apple was purely a hardware company they'd probably still be selling the XRaid. One factor with the XRaid is that over the network (where a SAN ha to live) it looks primarily like every other SAN box. Low chance for combined system differentiation and an increasingly commoditized product sector in relatively low volume .... cancel.
There are a few products that are not system like. Applications Apple sells, but those are run as proftiable, complementary businesses. The software they give away is purely complementary to complete the system (e.g., iTunes).