When it comes to death in the Harley Quinn cartoon, there hasn't really been that much on the heroic side. It's mostly the villains who have been killed off, as seen with Harley killing tyrants like Professor Pyg. It makes sense that the show wants to capitalize on heroes as much as possible, allowing a contrast to Harley as this vagabond vigilante who keeps crossing virtuous lines.
Source：https://www.cbr.com/harley-quinn-season-4-dick-grayson-death/
