He could be facing too many challenges in the fanfiction that seem insurmountable. In the Goblet of Fire, there are already many difficult tasks in the Triwizard Tournament. If the fanfiction added even more complex and dangerous situations, Harry might feel it's best to give up rather than risk his life or the lives of others.
Perhaps he realizes that the fanfiction is taking him in a direction that doesn't align with his true character. Harry is known for his integrity, and if the fanfiction was making him act out of character, he might give up.
It might imply that within the context of a Goblet of Fire - themed fanfiction, Harry Potter reaches a point where he can no longer continue. He could be tired of the events, or perhaps he realizes that the path he was on in the fanfiction was wrong. For example, if the fanfiction had him in a dangerous situation in the Triwizard Tournament that was getting out of hand, he might choose to give up to protect himself or others.
One reason could be the over - saturation of certain types of fanfiction. If there are a ton of fanfictions that follow the same tired tropes, like Harry always being the hero in the exact same way or his relationships being portrayed in a very clichéd manner, it could lead to this feeling of being fed up.
Fred and George Weasley are beloved in fanfiction. In the context of the Goblet of Fire, they could be involved in some wild schemes related to the tournament, like creating their own magical items to help Harry or just causing general chaos and hilarity around the events of the Triwizard Tournament.
One interesting plot could be an alternate version of the Triwizard Tournament where the tasks are even more dangerous and magical creatures from other regions are involved. For example, instead of just a Hungarian Horntail, there could be a whole nest of them to face in the first task.
It could be that he found the fanfiction community too chaotic or full of drama. There might have been arguments, or the quality of the works he was reading had declined, leading him to give it up.
Maybe he lost interest. Fanfiction can be time - consuming, and perhaps he found other hobbies or activities that were more appealing to him.
There's no real reason for the Potters to give away fanfic. Fanfic is a fan - created content, and the Potters are fictional characters. They don't exist in the real world where fanfic is created and shared.
One reason is copyright infringement. If the fanfiction uses too much of the original Harry Potter material without permission, it can be considered forbidden. Another reason could be that it contains disturbing or immoral content that doesn't align with the family - friendly nature of the original series.
One reason could be copyright. The creators and rights holders of Harry Potter want to protect their intellectual property. Fanfiction can sometimes blur the lines of ownership and might use elements of the story in ways that aren't authorized.
One reason could be copyright issues. The creators of Harry Potter own the rights to the characters and story, and fanfiction often uses these without permission.