Why is the fact that Ibn Umar believing it’s prohibited to Marry a Christian woman not more mainstream?

> Narrated Nafi: Whenever Ibn `Umar was asked about marrying a Christian lady or a Jewess, he would say: "Allah has made it unlawful for the believers to marry ladies who ascribe partners in worship to Allah, and I do not know of a greater thing, as regards to ascribing partners in worship, etc. to Allah, than that a lady should say that Jesus is her Lord although he is just one of Allah's slaves." Ibn Umar clearly believed it was prohibited to marry Christian woman due to her shirk. Before you say the Quran clearly it says it’s allowed to marry Christians so it doesn’t matter it doesn’t. The Quran uses the term People of the Book loosely. > “And He brought down those who supported them among the People of the Scripture1 from their fortresses and cast terror into their hearts [so that] a party [i.e., their men] you killed, and you took captive a party [i.e., the women and children].”- Quran 33:26 In this verse of the Quran Allah uses the term people of the book just for the Jews of Banu Qurayza. So Quran 5:5 can just be talking about Jews and Sabians excluding the Christians. Why don’t scholars adopt this view?