All these restaurants are run by people who have no real life experience in traditional Pakistani cuisine. They learn cooking from urban theories. Any Pakistani cooking, specially Punjabi ones without mustard oil as the principal fat along with ghee and butter are not authentic. Mustard oil and fried onions are two base elements. When you see raw onion which is not fried to golden brown is not authentic. Using tomatoes and methi indiscriminately in meat is not authentic either.
I never experience cooking in Mustard Oil. I am Punjabi ( Hazara, KPK. )
Travel and lived in different cities of Pakistan. Never heard of it.
First time having this statement.