Is it permissible to look at the hair and body of a non muslim woman, if not why?

From my understanding, non muslims are not held accountable for finer aspects of the Law like covering one’s awrah. And it is sinful to look at a muslim’s awrah regardless of if there is desire because it is part of their body God commanded to conceal. https://seekersguidance.org/answers/fast-shafii-fiqh/is-feeding-non-muslims-during-the-day-in-ramadan-permissible/ Also, scholars permitted people to view the breasts buttocks calves and other parts of the slave woman in the marketplace. This is evidenced by reports from Ibn Umar looking at these parts as well as Abu Hanifa’s opinion. عبد الرزاق عن ابن عيينة عن عمرو بن دينار عن مجاهد قال: كنت مع ابن عمر في السوق، فأبصر بجارية تباع، فكشف عن ساقها، وصك في صدرها، وقال: اشتروا، يريهم أنه لا بآس بذلك. Mujahid said that once Abdullah Ibn Umar came to a market where some traders wanted to buy a slave girl. Ibn Umar exposed her calves, then put his hands between her breasts and shook them. Afterwards he told the traders to buy that slave girl as there was no defect in her Given these things, is the only reason it is haram for a muslim man to look at the “awrah” parts of a non muslim woman because of the fear of fitnah? Similar to how some scholars prohibited slave woman to show these parts due to a similar fear. “Asked if it is reprehensible (tukrah) for slave women to veil in public, Aḥmad b. Ḥanbal replied that a beautiful slave woman should in fact do so (idhā kānat jamīla tantaqib)” (Anchassi, O 2021, Status distinctions and sartorial difference Slavery, sexual ethics, and the social logic of veiling in Islamic law) Originally cited: Al-Kawsaj (d. 251/865), Masāʾil al-imām Aḥmad b. Ḥanbal wa Iṣḥāq b. Rāhawayh, 10 vols.(Medina: al-Jāmiʿa al-islāmiyya, 1425/2004), 9: 4706; Abū Bakr al-Khallāl (d. 311/923), Aḥkām al-nisāʾ, ed. ʿUmar ʿAbd al-Munʿim Salīm (Beirut: Muʾassasat al-rayyān, 1423/2002), 60–61. Any insight into the legal rationale for prohibiting men from looking at non muslim women (hair etc) would be appreciated.