• We have updated our Community Code of Conduct. Please read through the new rules for the forum that are an integral part of Paradox Interactive’s User Agreement.
Thats a good question. However, i think that even in EU3 they could do that, add ruler's age, its what most of us want - some kind of dynasty system (or mechanics connected to ruler's age) that they didnt add.

The real question is what do you expect it to do in game, if it does nothing (EU3) theres no point in having it.
 
It would be awesome if there were some age-related bonuses. A bonus to administrative in later years, a bonus to military in earlier years. I'd like to see these stats change during a monarch's reign, instead of knowing how effective a monarch will be from birth to death as in EU3 (how does this 8-year old have 9 points in diplomacy!?)