There is no scientific or cultural basis for the claim that "Pakistanis act tough" as a group. Such statements rely on stereotyping — reducing 240+ million people of diverse ethnicities (Punjabis, Sindhis, Pashtuns, Baloch, Muhajirs, etc.), languages, religions, socioeconomic backgrounds, and personalities to a single behavioral caricature.
Pakistanis, like any large population, exhibit the full human range: gentle, anxious, assertive, vulnerable. Cultural values like ghairat (honor/dignity), mehmanawazi (hospitality), and family loyalty shape behavior — but don't dictate a monolithic "tough" persona.
Best practice: Judge individuals by their actions, not their passport. Curiosity and respect build understanding; stereotypes block it.