A vast, vast majority of the population could care less about learning about interrupts, tinkering with BIOS settings, etc. They want a device that is easy to use, and as simple as possible. So companies therefore abstract away 90% of the "creativity-inducing" components because a computer is a lot less intimidating when the user clearly knows what they can and can't do with it.
Apple and Google are not sitting in a meeting room pitching the best ways to stifle creativity. They are selling a product to a population that wants their highly complex device to be as simple as possible.