Draw. Sure, he can blow up planets and kill anything in his line of sight, but that isn't going to help against the Vex or Hive, who basically give a big -blam!-ing middle-finger to reality and manipulate time and space and reality as they please. Kill 10,000,000,000 Vex? Cool. There are more. There's also three different pocket-dimensions and alternate timelines where those same Vex still exist. There's also a SLIM possibility Goku might bump into a group of Gorgons or Oracles and be erased from existence before he can really figure out what's going on.