For a movie that's meant to represent the birth of a brand-new cinematic universe (the DCU), James Gunn's slight and slaphappy take on "Superman" doesn't feel much like the start of anything.  In part,

Zack Snyder gives James Gunn some unsolicited advice about his 'Superman' movie as the two cameo on 'Rick and Morty': 'He's the Man of Steel, not the Man of Conversation.'

David Corenswet's slightly puppyish Superman radiates a joy in what he's doing, but he’s far from invincible. That lends the film emotional stakes.