Atheon can lock people into different dimesnions/timelines. In another universe guardians don't exist at all the vex rule everything if you put thought into it. Goku also has a very hero's set of morals so he wouldn't have the conscious to be able to destroy a planet and walk away or fly with no problem gaurdians, vex, cabal, fallen, and hive are all soldiers some programmed to kill others bred to kill. The tone between characters and lore is to different to put up a real argument. We don't even know the extent of oryx's power yet if he's the father of crota it's only assumed that he holds immense amounts of power and is capable of destroying solar systems where as crota can take planets and moons over with ease. Goku also can be fatigued and get tired, where as an endless number of hive or vex don't feel fear or get tired so it's what ever way you want it to end to be honest. I'm also uninformed of the whole god mode thing but I've read from other users he needs other saiyans to achieve it and a the on can lock them all in different dimensions so that leaves normal saiyan goku alone to fight a universe that hasn't even been fully realized by the creators. dragon Ball z is to established to compete with destiny because destiny isn't even a year old yet and the universe is still growing.