By the time this review appears in print on Thursday, March 18, the web should offer many breakdowns of every single difference between Zack Snyder's Justice League and the 2017 Justice League, which is credited to Snyder but was largely helmed and written by Joss Whedon. So let's focus on how the two films are alike: Each, at the time of its release, could reasonably be called the most needlessly solemn, chore-like and joyless feature ever made about superheroes.