Re: Dupattaless culture
because it is hindu land too by its basic design, Saptasindhu, the area of pakistani punjab is place, where Hindu vedas were written. so people do convert but some part of previous religion remains intact. Indonesia’s airline name is after Hindu god Garuda, Iranian still celebrate Navroz 
It did occur, like chinese godless religion doesn’t allow Islam or Buddhism in its land even now. Even most of Congress and Bhagat Singh brigade was Marxist-Leninist in thought. It affected modern India very much, not sure about Pakistan though
Hinduism is religion of agriculturist people, that is why caste classification is classification of agricultural society. Every ritual or celebration marks climatic change. Sankranti (14th Jan) marks movement of sun from south to tropic of cancer to Deepawali (amavasya of Kartik marks beginning of Winter) to Holi (begining of spring) etc