> lock Macs down
But that's the thing. OSX, Linux, Windows--they're PC operating systems, and they run on PCs. Any PC. Which also includes virtual machine environments that emulate PCs. Apple could lock Mac hardware down, yes, but they can't stop a Hackintosh from running whatever it likes--because you wouldn't build a TPM chip into your Hackintosh.
Now, if your argument is that Apple is going to take OSX and make it into something that doesn't run on generic PCs, but rather a specific, closed environment that loosely resembles PCs [thus killing all ability to do Hackintosh builds, run OSX in a VM, etc.], I agree that there's a very slight possibility of that.
But Apple has a heavy incentive to keep OSX running on generic PCs. For one thing, it's required to maintain backward compatibility with all the current hardware that are just generic PCs. For another, it gives them the ability to test their software using generic VM products, rather than a specialized "simulator." For a third, it allows them to just construct a new prototype Mac in the lab out of the newest off-the-shelf components (picture an empty Mac Pro case with random hardware inside), and then use it to write and test drivers for those components, instead of waiting for a specialized mobo to be produced for them that supports all those technologies and carries their special, needed OSX TPM chip.
Sure, Apple could push the industry to standardize a UDID-carrying TPM chip for all devices (this is basically the dystopia everyone was scared would happen with Palladium), so that Apple could use off-the-shelf hardware and still do device-key deploys to it.
And sure, Apple could write their own machine simulator.
And sure, Apple could just make the device-deploy-keys feature optional until an OSX release where all the old hardware is no longer supported.
But why? What advantage does this give them? It sounds like a lot of hassle to create a world where it's harder for everyone--including Apple's own in-house developers--to develop, test, and distribute Mac software. A world where fewer developers want to develop for OSX. A world where it's impossible for enterprises (yes, Apple has enterprise customers) to deploy their own internal software over their networks.
Now, look out below, for :itisacaranalogy: --
If you're a car company who makes sedans [iOS devices] for "consumer driving", and trucks [Macs] for "utility driving", what purpose would it serve to turn all your products into cars? Especially if your own employees require a truck, as part of their job, to haul loads around the workplace?
As far as I can see, Macs are going to diverge from iOS, not converge. The more consumers who buy sedans [instead of buying a truck they don't need and then complaining when it doesn't have heated seats], the more "trucky" the trucks can become without impacting sales. Macbook Pros and Mac Minis--both "trucks"--are here to stay.
On the other hand, iMacs and Macbook Airs--both "sedans"--might just get locked down, run iOS, and probably have touchscreens one day. But that's just fine, isn't it?
The MBP looks like it's going to keep getting lighter until there's no need for a separate "Air" category any more; if they keep the brand after that, it'll be for an iOS device with a keyboard attached.
And the iMac is already a redundant competitor to (Mac Mini + Cinema Display); so it will probably make more sense as a big iOS touchscreen "kiosk." Instead of having a Mac built in, it'll have an Apple TV built in. (I imagine the Cinema Display would also get touchscreen capabilities, and then you'd get the same experience as an iMac by hooking an external Apple TV up to it instead of a Mac Mini.)
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...and note that everything I just said could apply equally well to Microsoft. They have all the same choices available to them, and there's already the same "nervousness" surrounding the Surface RT. It's just simpler to do the analysis with Apple, since their long-term hardware strategy is more obvious.