Here's why it was impactful:
* Emphasize the real-world impact of war: Fred's death demonstrates that even seemingly invincible characters, full of life and humor, can be victims of conflict.
* Deepen the emotional weight of the story: His death, alongside his brother George's survival, creates a stark contrast that emphasizes the fragility of life and the enduring power of grief.
* Illustrate the devastating toll on the characters: The loss of Fred deeply affects his family and friends, particularly his twin brother George, and adds another layer of sadness to an already tragic story.
* Reflect real-life loss: Many readers connected with Fred's death on a personal level, having experienced similar losses in their own lives.
While some readers found the decision to be cruel, it is ultimately a testament to Rowling's ability to create believable and emotional characters. Fred's death, though painful, serves a crucial purpose in the narrative.