What is the interpretation of someone dying while committing a sin, knowing that if they had lived, they would have repented?

Repentance and guidance come from Allah Almighty, and are His grace upon whomever of His servants He wills. The death of one person is not a definitive cause for another's repentance. Some may witness the demise of evil-doers and not repent, while others repent upon hearing the Qur'an and admonitions, or by associating with the righteous, without witnessing anyone's demise. Allah Almighty has clarified that guidance is for whomever He chooses to draw near to Himself, and He guides whoever turns to Him, meaning that the servant's good intention and diligence in seeking guidance are among the reasons for its facilitation for him.