Yeah I read that article last week, I think that tamper resistant software is going to be an addition to the hardware Rom chips that Apple usually adds to their hardware. And yep I think it is the same attitude that killed OS/2, and until Jobs leaves that same arrogance is going to continue.
As I said before, this may not be an issue of arrogance. It could be signs of something that apple could use a bit of- good business sense. If they keep their software limited , they avoid being seen as a direct competitor or threat to the microsoft monopoly. It can save them alot of trouble from M$ trying to keep control of the market, if they were ever to deem apple a threat. Also, it keeps them nice and friendly like, so M$ continues to make programs such as Office for the mac, so mac users can appear to be more compliant with the rest of the business world. Technically, Appleworks and iWork are supposed to work with MS Office type files, but you know how people are, they see that everyone else is using Word, so they have to use it too. It's hard enough fighting against the Windows mentality.
Now, secondly, OS X on any system out there could pose a problem for the Mac OS, since it's not designed to run on anything out there, it's designed to run on specific hardware. Run it on the vast plethura of machines out there, and there could be all sorts of bugs and issues that pop up that apple doesn't have the resources to support. It won't help their image if the other 95% start to use OS X on their Compaq and it crashes just like WinME.
It's possible that Apple is doing this out of a need to be anal and controlling, or perhaps out of arrogance, however, I'd like to think that there is at least a possibility they are finally getting smart in the business world and this is a sign that the will stop shooting themselves in the foot.