So two thoughts come to me after reading the summary and the comments
1/ This clearly demonstrates that Linux is the right technology to use when supporting business syetms with legacy hardware (I'll second the opinions that enterprise keeps hardware around the longest - I supported users on obsolete AS/400s which, whilst not as old as what some people here talk about, still mean we're frequently learning old technology in Support); and the point that the leadership (Linus right now, hopefully the same with whomever comes to replace him eventually!) can be more ameanable to keeping up support for old hardware is great. I dream of desktop uptake, but enterprise and research are where it's at.
2/ However I also wonder - isn't this an offshoot problem of the fact that Linux is a monolothic kernel? Can this kind of interface-specific support not be modularized? Say, an API/ABI (in-kernel)standard that allows the kernel to plough on with currently evolving requirements, whilst maintaining a stable interface for previously integrated kernel features that have been split off into modules...?
(and no, I'm not at all familiar with the ins and outs of kernel development and architecture - I just read newsposts and Wikipedia