Why did we not receive a clear and explicit interpretation from the Messenger of Allah, peace and blessings be upon him, such as Tafsir al-Jalalayn or Ibn Kathir, especially concerning the verses related to the unseen?

The Messenger of Allah, peace and blessings be upon him, explained what needed clarification and interpretation to the Companions who were contemporary with the revelation of the Qur'an. There was no need for other interpretations in his era. Rather, the need for such interpretations arose in later eras.