Couldn't agree with you more, until last summer when I finally went on the net I was blissfully unaware that certain so called Amiga users spent most of their time on these forums talking about everything else other than the Amiga... 
Sorry the rest of the community built horizons beyond the scope of the Amiga.
Anywhoo... just to inject a bit of irony here, anyone know how long an HD in an iMac should last, mines is only about 7 months old and it's failing with some message about "SMART failure occurring"... ruddy poxy piece of crApple junk... :angry:
Unless Apple went into the HD business and forgot to mention it to the rest of the world, it's highly unlikely that your HD failing is their fault. Back to your question... Consumer electronics should last around 4-5 years, obviously this will of course depend on how those pieces of kit were treated however.
Truthfully I'd not put much trust any hard drive on any system much beyond 3 years, even on a desktop system that is never moved. Sure, they can last years, even a decade or more, but as they get older the probability of their failing increases.
If your drive is registering a SMART failure, realistically it's time to replace it whilst it's still operable so as to prevent data loss. It's a warning feature that I would have killed for a couple of times with Amigas over the years... Live and learn I guess.