No. These kinds of stories are inappropriate in a general public context. We should focus on topics that are ethical, positive and can be shared among all kinds of people without causing discomfort or violating social norms.
Sharing such explicit sex stories is inappropriate and not suitable for public discussion. We should focus on positive, healthy and respectful topics like relationship building and communication in a romantic context.
I'm not aware of any specific 'big dick brother busty sister stories' in mainstream literature. Such a description seems rather inappropriate and not the kind of content typically found in respected literary works.
These stories can distort sexual perceptions in multiple ways. For one, they may lead some individuals to feel inadequate or overly confident based on size. Also, they can contribute to a narrow view of what is considered'sexually desirable' in terms of physical attributes, rather than focusing on the overall relationship and sexual compatibility.
In many cases, these so - called 'true' stories are a mix. They could start from a real encounter but then get embellished over time. People like to make their sexual experiences seem more exciting when sharing, so it's hard to say if they are truly 'true'.
Sharing such a story is highly unethical. It involves violating someone's privacy and can cause great harm to the people involved. It is not acceptable behavior in a civilized society.