all four current provinces (including Punjab) has that situation when you talk about economic, scientific, academic contributions. Hindus were ahead every where and that was the fear which finally lead to demand for separate country of Muslims.
Muslims in united India detested modern education (remember people like Sir Syed Ahmed Khan being termed as British agent). The story of low to no representation Sindhi Muslim middle class dates back to 16th / 17th century Afghan invasions (by Arghun and Tarkhan rulers).