Definitely, people are losing grip on language and that lead to inability of writing / saying things in witty way. During the suppressed and heavy censored era of Zia, we were able to produce good TV shows like Fifty Fifty, Aangan TeRha, etc and in literature people like Mushtaq Yusufi and Shafiq u Rehman were active, but now we are living in era of free media, but our humor has downgraded to cheap stuff like Qudusi Saheb ki bewah.
Loss of humor is also attributed to news channels creating havoc on incidents like a blast due fault in electricity transformer. They are promoting sad stuff with dedication and that had resulted in common men not able to understand or enjoy the humor.