Library science, information science and archival science belong to a system, and most colleges and universities classify them as information management. My teacher told me that among the three majors, information science actually has the widest employment scope, and you can feel it from the name.
Library science into the library, archives science into the archives bureau, all need to pass the exam, which is the only way to enter the institution.
If we choose a wider employment direction, library science can consider information industry, consulting industry and so on. Archival science now focuses on e-government, and it is a good choice to apply for civil servants.
In fact, it doesn't matter which of the two majors is better for employment. It mainly depends on what kind of work you want to do in the future.
PS: We often discuss this issue with people majoring in archives. In the end, it seems that there is no clear result, because everyone basically does not engage in work related to their major.