I just went by the Google translate without thinking. It seems that in Japanese baseball the rookie of the year award is referred to in this way. Winning this tournament is probably a good indicator that someone will be among the top players in a few years. Maybe it's similar in that way to the rookie of the year award.

Even "new players champion" could be something of a misnomer. The rules of the tournaments in recent years are that players must be under 25 and less than 6 dan and not have won the tournament. Before 2007 there wasn't this restriction on former champions competing again. Yoda Norimoto and Yamashita Keigo, for example, won repeatedly. The winner will often be someone who was already a pro for some time, especially with 9 year-olds becoming pros these days.