Hmmm, does it not lose it's antifreeze properties then? I know the older blue stuff only had a life span of 2-3 years before it became ineffective.
Anti freeze does not loose it 'anti freeze' qualities, unless it has been diluted by topping up with water.
The older stuff would loose its corrosion properties and needed changing on a regular basis. The chemicals used for anti corrosion and the materials used in the engine and other components have negated that.
VW quality antifreeze is 'good for life' whatever that means.
It wouldn't hurt to change, but I doubt it's needed - with a certain amount of replenishment every time a cam belt / thermostat etc is changed!