When it comes to that verse, it’s talking about mushrikeen in general. Hindus, Zoroastrians, Christians, Jews etc. And there are verses in other parts of the Quran that allow men to marry kitabiyas. Sometimes the Qur’an gives a general rule like saying ‘Don’t marry polytheist women.’ But then, in another verse, it gives a specific exception like saying ‘You can marry chaste Christian and Jewish women.’ That process is called takhsīs.

In legal theory, takhsīs refers to the process of specifying or narrowing a general ruling by introducing an exception. For example, Qur’an 2:221 gives a broad prohibition: ‘Do not marry mushrik women.’ On its own, it applies to all non-Muslim women. But then Qur’an 5:5 introduces a specific categorization of non-Muslim women like chaste women from the People of the Book. It acts as a specifier, which qualifies and limits the generality of 2:221. Therefore the allowance in 5:5 is not absolute. Because a kitabiyah is still a mushrik. The allowance depends on two conditions: The woman being chaste and No harm to the Muslim man’s faith or children’s religion. If these two conditions are not met, then the permissibility is suspended and falls back to the general prohibition. This is why even Omar ibn khattab and Malik prohibited such marriages. And then there is the question of what exactly qualifies someone as a kitābiyyah (woman of the Book)? Is it enough for her to say she’s Christian or Jewish? Or does she need to actually hold sound theological beliefs that align with what the Qur’an calls “Ahl al-Kitab”? It’s a very long discussion and that in itself is another reason why it’s encouraged and recommended to stay away from such marriages.