Contrived is a bit uncharitable. 5 year old hardware (which would be around the calibre of a Core Duo with 1Gb ram?) is still perfectly serviceable for your average office worker.

With Linux they have the choice to defer hw upgrade until it's justified for reasons other than 'we need to upgrade the OS and because the current hardware came with an OEM licence and so is not covered by any volume licencing deal that may be in place (without spending extra) its cheaper to buy a new PC with a Windows bundled than it is to just buy the software upgrade then the hardware when it's really needed'.