The skill trend

It's common to see that until their early 20s, players' skill increases rapidly. However, skill plateaus at roughly 35, then slowly decline. Most players peak at more-or-less 40.

Today's top players all seem to be young? What does this mean?

The average age of the top 20 players in the open category is 32. It could mean that younger players are better in decision making, mental fitness, which leads to better move-making.
Mental fitness indeed is one of the most significant elements in the game. Of course, younger players could be better because of their ability to adapt to new training methods, better memory(when a player can remember more positions, it is much easier to decide the moves).

What about the positives?

"Experience is the teacher of all things", said Julius Ceasar.
With age comes experience, along with experience, comes knowledge and with knowledge comes excellence.
Time also brings upon maturity. Maturity matters not just in life but can also be important in other fields like chess.

It's also psychological.

If a 36-year old is on a bad run, fans and pundits alike will blame it on his age. The same can also be applied vice-versa.
"When you're young, it's easy to ascribe a spate of poor results to nothing but performance clefts. But as I progressed into my mid-forties, such explanations became implausible. The 'phase' of poor showings had dragged on for too long, with no climbs or crests insight. The damning bit was that I struggled to remember details - it was almost like they'd fallen off my head like Jenga pieces. I'd never felt this kind of lull before. It occurred to me for the first time that this could be something else after all."
Taken from Mind Master, by Vishwanathan Anand.

What about retirement?

Players retire after they feel they are not fit enough to continue playing. Most players hang up their boots after they start to think that they can improve or make progress. Others retire because of physical health and/or mental conditions which come with age or some cases, a bad financial state.
Most of the reasons are age-related. As mentioned at the starting, players peek at a certain age. Players tend to peak at a certain age.

That's it for now. Please like if you liked this post. Bye!