After being resurrected, Superman dons a black and silver version of his costume, as the hero is wont to do after coming back to life. DC Comics killed Superman in the 1992 Death of Superman storyline, but he returned in 1993, emerging from a Kryptonian birthing matrix sporting a noir version of his classic outfit.
Superman’s black suit, also known as the Recovery Suit and sometimes the Regeneration or Solar Suit, was first introduced during the comics’ Reign of the Supermen storyline, which followed The Death of Superman. As its name suggests, the purpose of the suit was to revitalize the wearer. In particular, it absorbed more solar energy than a Kryptonian, in this case Superman, normally would as their body recovered to again work at a normal level. Via cbr.com
It’s unclear if the Snyder Cut’s Superman is wearing black for the same reason. More likely it’s just an homage to comics history and a chance to bring a fan-favorite alternate costume to the big screen. Via Vulture
One thing that really stood out to me with the Snyder Cut is that Zack Snyder clearly respects the character of Wonder Woman and also the actress playing her, Gal Gadot. All the disgusting, demeaning shit Whedon tacked on to his version with the gross camera angles, Barry falling into her boobs, Aquaman lusting after her, the awkward flirty scenes with Bruce… it’s all completely absent from Zack Snyder’s version. And the conversations and interactions Diana has with everyone in the Snyder cut are so much more meaningful and interesting than the slop Whedon gave us
