Why did some of the Salaf, such as Omar, Ali, and Ibn Masoud, may Allah be pleased with them, say that the sacrificed son was Isaac, even though the Quran indicated that he was Ishmael?

The early Muslims (Salaf) differed regarding the identity of the sacrificed son. Some said it was Isaac, and some said it was Ishmael. Many scholars, such as Ibn Al-Qayyim, Ibn Kathir, and Al-Shanqeeti, preferred the view that the sacrificed son was Ishmael, peace be upon him. They based this on the Quranic verses that mention the glad tidings of a forbearing boy before the story of the sacrifice, then mention the glad tid tidings of Isaac afterwards. This indicates a distinction between the two boys. Additionally, the narrations indicating that the sacrificed son was Isaac are weak, and the claim that it was Isaac is derived from the People of the Book, contradicting their own scripture which states that the sacrificed son was the firstborn, who was Ishmael.