Why is chess dominated by relatively young players? The top FIDE rated players (2700 chess) are all under 50 years old. Most of them seem to be around the 23-32 age range. Why is this the case? I don't really know if this has always been the case or if it this is just something apparent in the current generation.

I'm guessing this is the case for a number of reasons that may include:


Leaving chess
Lacking needed attention
Lacking stamina
Impaired memory of positions and theory
Well, all you mentioned are probably the reasons for some players.

I would also add 'lack of time' as one of the reasons. When you get older you may need to go to a college/university (chess don't bring much money, unless you are at the top), then family life/kids (chess players have to travel regularly a lot) makes travel harder... So, many people 'switch' to teaching and playing only in local tournaments.