This is one of my favorite topics. In addition to the above, without any single doubt, being dominant enables a player to develop unique abilities.
My best argument for this is Mario Lemieux. Look at his production in 01'-03'. Scoring in the NHL is record low, he scores 76 pts in 43 games in 01', 91 pts in 67 in 03'. Someone will say, but he was that great, Mario was unique. The thing is, lol, he was god awful in many areas IN 01'-03'. He could barely skate. He was 6'4 and hadn't played for 3 years. 35-36 y/o. It was a bit extreme, but in 02' only 4 players scored more than 80 pts in the entire league.
Mario was literary looking like a man among boys. Serious experts were questioning if the games he played in was rigged, how could he dominate that much despite being one of the worst skaters on the ice, had poor stamina? It of course shows if you haven't played in 3 years. Rusty like heck.
The thing is just that he came into the NHL at a time the level of play was so low, that he was really dominant with his generational talented skill set in 1984. While the NHL raised it overall level super rapidly in the early 90's when the eastern block fell, europeans started to join the league, and when the athleetes went from half-pros to super devoted pros in the 00's -- Mario could adjust and still stay on top of things. Nobody can develop like that anymore, unless they find a way to "jump ahead" from when they are 18 y/o.
My point is just, sometimes the early bloomers, players born early, benefit a lot from just that. They get a ahead and stay ahead. Its much harder to come from behind, you have never been dominant and hence never learned how to be dominant, if that makes any sense.