Perhaps in certain fanfictions, the author is trying to make a statement about how institutions can sometimes be unjust. Gryffindor, which is seen as a noble house in the original books, might be portrayed as making a wrong decision in banning Harry. It could be a way to show that even the 'good guys' can make mistakes. Also, it might be a creative way to introduce new conflicts and alliances for Harry that he wouldn't have if he was still in Gryffindor.
There could be many reasons. Maybe some fanfiction writers want to create an alternate universe where Harry has a different path. It could also be for the sake of creating a more complex and unexpected plot, like having him be falsely accused of something so bad that Gryffindor doesn't want him. Another possibility is that the writer wants to explore how Harry would react and grow outside of the Gryffindor environment he's so closely associated with in the original series.
He might feel a great sense of betrayal. Since Gryffindor was like his home in Hogwarts, being banned could make him question his identity. He could become more isolated and withdrawn at first. However, this could also lead to him finding new friends and allies from other houses or even outside of Hogwarts.
One possible reason could be copyright issues. The original creators and publishers might want to have strict control over the Harry Potter universe to protect their intellectual property. They may be concerned that fanfiction could potentially distort or misuse the original concepts and characters in ways that are not in line with their vision for the franchise.
There could be several reasons. One is simply to add drama. A lot of fanfiction writers thrive on creating conflict, and what better way to do that than by taking on one of the most beloved houses in the 'Harry Potter' series? Another reason might be personal bias. Perhaps the writer had a negative experience with someone who identified strongly with Gryffindor, or they just don't like the traits that are typically associated with Gryffindor, like impulsiveness, and they use fanfiction as a way to express their views.
Well, it could be that the fanfiction writer is trying to subvert the traditional narrative. Harry has always been the hero of Gryffindor, but in this new take, he hates it. Maybe he sees the flaws in Gryffindor that are often overlooked in the original story, like the over - emphasis on courage which can sometimes lead to recklessness and he doesn't like being part of a house with such a one - dimensional view of what's important.
In some fanfictions, Gryffindor might kick out Harry Potter due to false accusations. Maybe someone spread rumors that he was using dark magic or endangering the other students. It could also be a plot device to create a more complex and different storyline from the original, where Harry has to fight to prove his innocence and regain his place in Gryffindor.
Maybe it's to fit certain moral or ethical standards set by the fanfiction community. For example, some interpretations of Harry's character might be considered too dark or out of character, so they censor it to keep the overall tone positive and in line with the general perception of Gryffindor values.
In some fanfics, Harry might be made to hate Gryffindor perhaps because the author wants to explore an alternative personality for him. Maybe they want to show how the Gryffindor house's values, like bravado or recklessness, could be seen in a negative light from Harry's perspective.
Yes, in some fanfictions, Harry Potter is depicted as the heir of Gryffindor. It adds an interesting twist to the original story. The connection to the Gryffindor sword becomes more profound as it is often a symbol of Gryffindor's legacy. In these fanfictions, Harry might discover hidden powers or a deeper understanding of his destiny through this new identity.
One possible reason could be a false accusation of using dark magic. In some fanfictions, the wizarding world can be very paranoid about dark magic, and if Harry was wrongly suspected of delving into it, Gryffindor might exile him to protect their reputation.
One possible plot could be that Harry is framed for something he didn't do. Maybe a powerful dark object is found in his dorm, and the Gryffindor house, fearing for their reputation and safety, decides to exile him. Harry then has to prove his innocence while also dealing with the isolation and new challenges outside of his familiar house.