Well, then you can enjoy your teletype there grandpa.
I hate to be the one to break it to you, but functional obsolescence has always been part of technology, the only difference is the time window. This window will continue to get shorter no matter what brand you buy, because technological innovation is growing at an ever faster pace.
What has helped make Apple the most valuable company in the world, is partially due to the fact that they are not spending dollars are obsolete technologies, they have made it very clear that when something is no longer viable to them, they will move on.
Could you get ios 8 to run on your 4 year old iPod Touch? Sure, but it would be so slow that it would be unusable. At a base simplistic level processing power doubles on every 2 years so your iPod Touch is 1/4 as powerful as a new device.
Its the reality of the world... You think this is just an Apple issue? Not at all, go fire up a 2011 Droid smartphone and even if you can get the latest version of Android to run on it and tell me how much you like it.
I’ve been in tech for over 30 years, the idea that you are going to buy a dedicated computing device and expect more than a 5 year lifespan out of it are virtually done. Laptops/PC’s perhaps, but everything else? Nope.
That's actually truer than you know. My cell phone is a nine year old flip model, my watch is a mechanical Breitling which I bought used in 1997 and which I'll probably be able to hand down to my son, and I own no "tablets" of any kind.
Of course there's no reason why that should be so, except for cynical planned obsolescence.