"on a laptop you'd certainly expect to be able to run linux."
The fraction of end users to whom it would occur to consider Linux on their laptop is tiny. The fraction of consumers who would consider it is even smaller. The fraction of consumers who would expect their new laptop to support Linux is negligible. The expectations of the HN community are atypicle.
And regardless, you can, rightly, expect a laptop to be able to run linux (albeit you can't expect it to be quirk-free).
You can run linux and other operating systems on many phones and tablets as well. But the fraction of those that consider that is waay smaller than for a laptop (and I doubt anyone would expect it from a typical phone/tablet). As well as the result being barely usable and more of a proof of concept in the very most of the cases.
To clarify: Based on current trends regarding hardware, e.g. the "post PC era", and software, e.g. "walled gardens"; an expectation that in the future one will be able to run the OS of their choice on common computing devices with the sanction of the hardware manufacturer increasingly looks less reasonable.
Yes, it is possible to boot Linux on an iPad. And it is also likely that one will be able to likewise boot Linux on devices using the new Intel parts.
But this does not make for a reasonable expectation that end users (let alone general consumers) will have a viable practical alternative to do so in the future. In general the trends are in the other direction, particularly in regards to hardware being configured as general computing devices rather than having systems more firmly embedded.
A few years ago, Napster, made it look as if music would be freely distributable. A few years before that, there was no advertising on the internet. Earlier, commercial software was shareable among people who did not purchase it. At one time computers filled large rooms.
The trick is that there are two different sorts of "expect".
Suppose a parent finds their teenage kid watching TV instead of studying for an exam and says, "I expect you to do well on that exam tomorrow!". Do they expect their child to do well? Yes. Do they expect their child to do well? No, they would be foolish to.
At the present, both types of "expect" apply to this discussion. Some companies seem intent on eliminating one of those expectations, but they cannot do anything about the other.
The fraction of end users to whom it would occur to consider Linux on their laptop is tiny. The fraction of consumers who would consider it is even smaller. The fraction of consumers who would expect their new laptop to support Linux is negligible. The expectations of the HN community are atypicle.