(1) Online game databases have made it easier for players to track developments in opening theory and prepare to play specific opponents
(2) Chess engines add to this be used to search for antidotes to complicated opening systems
(3) Young players have greater access to high-quality sparring partners - either engines or fellow humans on online servers.
This has lead to the best players becoming younger, and players playing more varied and less 'sharp' openings.
(1) Online game databases have made it easier for players to track developments in opening theory and prepare to play specific opponents
(2) Chess engines add to this be used to search for antidotes to complicated opening systems
(3) Young players have greater access to high-quality sparring partners - either engines or fellow humans on online servers.
This has lead to the best players becoming younger, and players playing more varied and less 'sharp' openings.