His departure can have some positive impacts too. It might force the wizarding community in Magical Britain to become more self - reliant. Instead of relying on Harry to save the day all the time, they could start developing their own defenses and strategies. Politically, it could lead to a change in the power dynamics. Some groups that were previously overshadowed by Harry's presence might come to the forefront. In the long run, it could also inspire a new generation of wizards to step up and be heroes in their own right. They would see that they can't always depend on one person to keep them safe. However, there could also be a period of instability as different factions try to fill the void left by Harry.
In fanfiction, Harry's departure can change the relationships within the wizarding world. His absence could lead to the strengthening of some friendships as his friends band together to deal with the situation. On the other hand, it could also cause rifts as some blame others for his leaving. The Ministry of Magic might face a crisis of leadership as they try to figure out how to handle the situation without Harry. There could be a shift in the economy as well. For example, if Harry was a big part of the local magical economy through his fame and influence, his leaving could have a negative impact on certain businesses. And the overall culture of Magical Britain could change. Without Harry as a role model, the values and ideals that the wizarding youth look up to might shift.
Well, his departure can cause a great deal of chaos. For one, the wizarding world in Magical Britain might lose its most powerful protector. Without Harry, there could be a resurgence of Dark Magic as villains might feel emboldened. His friends would also be deeply affected. They might be left feeling abandoned and less confident in the fight against evil. Also, the public's morale could take a huge hit. Harry was a symbol of hope, and his leaving could make the general wizarding population feel less secure.