Chad Buddha fucking up everything just cause he can, and adding to that is the seven lucky god's transformation scene making everyone go "WHAT THE FUCK?!?".
Also of course the author would not scale their powers accordingly to their mythos. Going by mythology, Shiva is actually more powerful than Zeus and Odin combined by miles since he can just open his eyes and destroy Olympus and Asgard, but here he almost got his ass kicked by the heroic wrestler duo in this manga. If we were to scale them accordingly to their mythology, the human side would have zero chance in beating any of the gods. Also, Zeus ain't even the strongest god in his mythology, he shat his pants multiple times cause of Nyx and a bunch of other primordial gods, while Odin died due to being unable of overcoming his fate of being eaten by the God Eating wolf Fenrir.