I don’t think you can hold Apple accountable for a three year old technology losing some capabilities through all these software updates. Tech jus doesn’t last that long anymore. I rarely have a laptop last more than two years. My droid phones were obsolete in their third year. The pace of software advancement matches or exceeds the advancement of the chips and hardware.
While I don't necessarily agree with this, I can certainly hold Apple accountable for not informing me that installing the latest OS upgrade would affect performance substantially and thus giving me the opportunity to make an informed decision as to whether or not to install the update. Had I known about this I would never have upgrade as the tablet was already doing everything I needed just fine. The failure to do this was a conscious decision on Apple's part, intended to force me to buy a newer product.
These days processors are stupidly powerful for the vast majority of user's needs.
I just don't understand how any reasonably decent modern processor can become 'underpowered' in just a couple of years. Buy decent hardware and enough capacity (RAM/Disk) and a 6 year(or more) lifespan is easily doable unless you're trying to render movies for ILM.
The last desktop I built was designed to be a 10 year box (it's now about 3 years old). I started off with top of the line hardware, knowing that over time it will age gracefully, and eventually will get to the point where some new and shiny 24-48 core system will simply offer so much processing power that it would be stupid for me not to upgrade, especially when I can match the processor to similar increases in memory capacity.