It would be cool seeing plastics things rot, though. We're used to them being impervious.
Even if you are an outlier in terms of keeping tech a long time, upgrading internal components etc, there is very little chance rotting plastic will be the reason you laptop fails.
Oh wait! They use protective finishes to seal out the environment and bacteria that would eat the wood, so it doesn't go bad.
They do the same with aluminum and titanium. Hell, they even do this with steel.
The concept of applying a protective finish has been a solved issue for literally centuries...
http://hn.premii.com/#/article/15977640
I suspect plastic will take significantly less time than cellulose though. It's an amazing material, and the biodiversity of the planet (though shrinking) is still much higher than it was when cellulose began proliferating.