Children’s shows have to depict death and “evil” in specific ways for it to air. The theme of Steven Universe and many similar shows rely on the fantasy of anyone and everyone being capable of change for the better. It simply wouldn’t make sense for Steven to kill the big bad at the end.

Do I think writers brought about some implications that are particularly dark? Sure, but adults see ALL children’s media as dark and scary, but children don’t. They don’t see a kid walking off alone into the woods as a threat, but as an adventure.

While it may be extremely melodramatic, overblown, too dark, etc., the Diamonds depict a variety of reactions to grief that children can understand. Which is the main point of their characters and redemption.

(Also, it’s pretty clear that gem life is inorganic, which, like the Rattleballs in Adventure Time, is used to intentionally lessen the blow of death and violence.)