I am sorry but that cannot be correct. US anti-trust laws would never allow any such deal. In any case the Apple OS is only good for people with limited needs and would never ever be able to compete in an open market. Personally I find their computers and OS to be, how should i put this withotu being rude, designed for the simple minded.
From what I know, Apple used to do parallel internal x86 builds of their OS even when they were running on PowerPC architecture. They migrated to x86 (strictly speaking, Intel) only because they realized that PowerPC was reaching an evolutionary dead-end. So, one fine day, Steve decided to take the step, plus Intel was courting them for a long time and also offered them a sweet deal.
The reason why Apple has not released a stand-alone version of their OS is because they are primarily a "product" company - the fact that they happen to make both hardware and software is only a by-product of that (pun unintended). As per Apple's vision, selling their OS without selling their hardware makes as much sense to them as Honda selling steering wheels as that will fit onto other cars.
The problem is that the technical literati is not used to this. They are used to computers being a motley grouping of assorted hardware and software components, thus requiring arcane knowledge of such technical details, and with the independence of customizability and inter-operability.
Products or devices on the other hand are all about usefulness, ease of use, compactness, build quality, etc. They are mostly "closed systems" where we accept the product for what it is and buy it in a finished, not disassembled state. Imagine if you had to periodically open your microwave to update your firmware, or if you had expectations of your toaster to provide programmable custom heat settings in addition to the ones provided to you by the dial.
In short, Apple makes products. They are very good at making products. This does not mean that they necessarily make the best OS, user interface, or hardware. However, they do consistently make the best packages of these components, as evidence of their sales and brand image suggests.
In short, if my grandma wanted to buy a computer and wanted to know how to "download the internet", my choice would always be Apple. If you look at the complexity of technical gadgets that surround us nowadays that requires even hardcore geeks to pore over manuals, online forums, and web pages to know how to properly operate a daily use item like a television or a microwave, you know we are in trouble.
Apple simplifies the world for a normal person, and this is why it succeeds. Forget grandma, I myself would prefer usability over features. Give me a big fat knob or an on/off switch anyday over a bank of buttons or snazzy touch interfaces.