The difference between MCU and DC villains.

Going back to the characters as they existed in their comic book origins as I read them in the 1960s, EVERYTHING  was formulaic. Bad guys were bad guys. Good guys were good guys. No real backstory. 
I have an early Thor where Loki attacks Thor as the son of Odin, Loki's enemy. No brother stuff mentioned. 

They were all wish fulfillment. Drink a potion, become Captain America. Shoot a few arrows & become Green Arrow or Hawkeye. They were kid stories like Saturday Morning Cartoons. 

All the rest is machinations to make them appeal to an older audience 

Steve Rogers was the 98 lb weakling who had sand kicked in his face figuratively until a magic potion made him a hero in an era many now can't comprehend, an era where boys lied about their age to join the army. His spirit was willing, but his body weak until science fixed it.
How the HELL is that not an arc?