Nastaliq Urdu is not an appropriate choice for default Arabic
The choice of Nastaliq Urdu as a preferred font for Arabic is not acceptable. These types of fonts are unreadable for the vast majority of Arabic readers. You don't need to be Arabic to see the difference in legibility between an Urdu and a Naskh font. Look at the images I've attached.
The file in question is conf.d/65-nonlatin.conf
. Serif arabic should prefer a Naskh font like Noto Naskh Arabic. Sans Serif should prefer a sans font like Noto Sans Arabic.