Me. If the May duelist is Syrus, then that is an 🔥 to Zane. Zane's roaming event was first and he is an iconic character to GX. Plus, if anyone is looks ready to take on the world, it is him!
I feel like Konami is purposely taking their time with some characters (Zane, Marik Ishtar, Espa) because they might be afraid that the cards they have (Jinzo, Necrovalley...and now Cyber Dragons!?) would hurt the game. That is ridiculous if that is true. Plenty of ways to deal with these cards. But they must know that Zane is not someone that they can get away with not adding for too long!
I think that it is probably Syrus. But it is worth noting that the Japanese pronoun "boku" is also used by Marik Ishtar. But overall, the speech pattern sounds more similar to Syrus, and I can imagine him saying that he is ready to take on the world when he gained more confidence in the anime.