The wizarding world might be very concerned. Dumbledore would surely keep a close eye on Harry. There could be secret attempts to check on him without the Dursleys noticing. Wizards might be worried that the Dursleys would influence Harry negatively, especially regarding his views on magic.
The wizarding world's reaction could be mixed. Some might be appalled at how the Dursleys treat Harry, while others might be more patient, believing that in the end, Harry's true nature will shine through. There could also be a lot of speculation about what kind of wizard Harry will become. Will he be more in touch with the Muggle world? Will he be more cynical because of his upbringing? All these questions would swirl around in the wizarding community.
Some in the wizarding world might think that leaving Harry with the Dursleys was a mistake. There could be a group that tries to rescue Harry earlier. But others might believe that it's all part of a grand plan and that Harry will emerge stronger from this difficult upbringing. For instance, they might think that his experience with the Muggles will give him a unique perspective when dealing with certain wizarding issues.
They would be devastated. Harry has many friends and allies. People like Hermione and Ron would be heartbroken and would probably seek revenge. The Hogwarts faculty would also be deeply affected. Dumbledore, if he's still alive in the fanfiction, would feel a great sense of guilt for not protecting Harry better. There might be a split in the wizarding community, some believing the Dursleys were acting on their own, others suspecting a darker conspiracy.
The wizarding world would likely be in shock. Harry was seen as a hero, and this act would completely change their perception of him. Some might think he was finally getting revenge for all the abuse he endured, but many would condemn his actions as murder is still a serious crime in the wizarding world.
The wizarding world's reaction would be complex. On one hand, Harry's friends like Hermione and Ron might be conflicted. They know the Dursleys were awful to Harry, but they also believe in the value of life. Wizards who have a strong sense of justice might understand Harry's actions, especially those who have also faced prejudice or abuse. But the more traditional and law - abiding members of the wizarding community would condemn Harry, and the Ministry would likely try to arrest him, leading to a possible conflict between those who support Harry and those who don't.
The Ministry of Magic would be in a difficult position. On one hand, they would need to keep the wizarding world calm. On the other hand, they would have to deal with the fact that a muggle family killed a famous wizard. There would be debates about how to handle the Dursleys. Some might want to obliviate their memories and send them to Azkaban, while others might think that a more public trial is necessary to show that the wizarding world does not tolerate such actions against one of their own.
Some might be angry, thinking he's abandoning his responsibilities. The Ministry of Magic might try to persuade him to come back or even use force if they thought it was necessary for the safety of the wizarding world. His friends, on the other hand, would likely be sad and try to understand his reasons. They might also try to convince him to return, as they know how much he means to the fight against evil in the wizarding world.
There would be a great deal of shock and confusion. Many would start to question everything they had believed in. Families would be divided. Some might think that Harry had been corrupted by Voldemort's dark magic and try to find a way to reverse it. The Ministry of Magic would be in a panic. They would try to come up with new strategies to deal with this new threat. Teachers at Hogwarts would be worried about the safety of their students. And the Death Eaters, while initially happy to have Harry on their side, would also be suspicious of his motives and loyalty.
The wizarding world would likely be in shock. Harry is seen as a symbol of hope against Voldemort. His death at the hands of Vernon would be a huge blow. There would probably be a lot of anger towards the non - magical world for allowing such a thing to happen.
There would be shock and disbelief. The wizarding world has always seen Hogwarts as a symbol of hope, knowledge and safety. If Harry destroys it, many would be in denial at first, thinking it couldn't be true. Wizards and witches from all over would come to the ruins, trying to figure out what had happened.
The wizarding world would be in shock. Harry is seen as a hero, and for him to kill Draco, even if Draco was from a 'less popular' side, would be a huge scandal. His friends like Hermione and Ron would be deeply conflicted. They would be torn between their loyalty to Harry and their disbelief at his actions.
The Ministry of Magic would probably be in an uproar. They might see Dumbledore's actions as a blatant abuse of power. They would send out Aurors to search for Harry and arrest Dumbledore. After all, Dumbledore is one of the most powerful wizards, and his actions would be seen as a threat to the stability of the wizarding world.