Its possible for your PS2's laser to die over time, or rather any consoles laser will fade. I had it happen to all 3 of my last gen systems. The gamecube was an easy fix since you could open up the system and crank up the power on the laser.
This is my least favorite aspect of the newer game consoles. Gone are the days of keeping your beaten-up SNES around for 15 years and having it still work like new. Whereas the older systems were fully solid state, the newer ones have laser lenses and moving parts, both of which will degrade and stop working in 4-8 years, tops.
And unless the manufacturers keep the string of backward compatibility going (which, based on their recent moves, it looks like they won't), what we'll all be faced with, eventually, is a situation where the old consoles aren't made anymore and can't be fixed...so we're stuck with a bunch of old games we've no way to play anymore.