I think this example only solidifies gp's point. It sounded to me like they were talking about the ability to open up the laptop and actually repair it, which it seems even Microsoft can't do with their own machines. Full replacement from support is convenient, but what if I just want an extra 16GB of RAM?
They can do it with their own machines, as the replacement I got was a refurbished one (with a different model of battery installed). My original machine was irreparable as the battery expansion had damaged the screen and warped the metal of the case itself! I agree they're not serviceable by mere mortals, though, and many upgrades are impossible.
I have a Thinkpad X201 Tablet from 2010, and it's easy to take it apart and replace/clean bits. There's a serious cost to that, though: the entire Surface Pro 4 tablet takes up only about the volume of the Thinkpad's screen. The Thinkpad as a whole is about three times that thickness. This is only partly an age thing - mostly it's serviceability design.
