It could also be due to a clash of ideologies. Tony is a scientific genius and has a very practical and sometimes self - reliant approach. If the other Avengers have a more idealistic or group - centered ideology that constantly clashes with his, he might just lose his patience and kick them out.
Thor could be angry. He's a proud warrior and being kicked out like that might be seen as an insult. He might even challenge Tony in some way, either verbally or physically. However, he also has a sense of honor and might listen to Tony's reasons if given the chance.
One possible reason could be a major disagreement. Maybe the Avengers made a decision that Tony strongly opposed, like a dangerous mission plan that he thought was too risky. For example, if they decided to team up with a morally ambiguous character without proper precautions. Another reason might be personal issues. Tony could be going through something in his personal life that makes him want to distance himself from the group, like dealing with the stress of his identity as Iron Man being public and feeling the Avengers draw too much unwanted attention.
Perhaps it's due to personal relationships. He might have had a falling - out with one or more of the other Avengers. Like if there were misunderstandings or betrayals. In some fanfictions, a conflict with Steve over leadership or ideological differences could lead to Tony leaving the team.
Differences in ideology can also play a part. Tony might have some views on how to handle threats or use technology that the other Avengers don't agree with. Maybe he's more willing to take risks with untested tech that could endanger the team or civilians, which would lead to resentment.
There could be some legal issues involved. Maybe there are new regulations or copyright concerns that make it difficult or unwise for him to continue paying for Avengers fanfiction. It might be that the original creators of the Avengers franchise have put some restrictions that prevent him from financially supporting fan - made works.
Tony Stark may dislike Avengers fanfiction because it can mess with the emotional core of the team. The real relationships between the Avengers are deep and complex. Fanfiction might simplify or distort these relationships. For instance, his friendship with Steve Rogers has many layers, and fanfiction could make it into something that doesn't do justice to their real bond. Also, he's a man who values his privacy to an extent. Fanfiction might delve into his personal life in ways that he doesn't appreciate, making him feel exposed and misrepresented.
One reason could be that he's frustrated with the leadership or the direction the Avengers are taking in the fanfiction. He might feel his ideas are not being heard.
He might dislike it because it can create false expectations. Fans read fanfiction and might start expecting the real Avengers to act in a certain way that is not in line with their true nature.
One possible reason could be that in the fanfiction, the wizarding community in England has turned against Harry due to some false accusations. Maybe a powerful dark wizard has framed him for a series of heinous crimes, and the public, being misled, forces him to leave. Another reason might be political intrigue within the Ministry of Magic. There could be a new regime that sees Harry as a threat to their power and thus kicks him out.
One possible reason could be jealousy. Maybe Tony's intelligence and wealth made some Avengers feel inferior, and over time, that festered into betrayal. For example, if Tony developed a new technology that could potentially overshadow their own abilities, they might feel threatened.