Oh, it does seem plausible that Muslims invented it. But perhaps not the sort of Muslim that Pakistanis nowadays would recognize as Muslim; this was during the period of free inquiry in Islam, before
Al-Ghazali shut down inquiry into the natural sciences.
Think about what would happen if distillation wasn't discovered centuries ago but by a Pakistani today. Wouldn't the reaction be, "A new temptation to get drunk, even stronger than wine? He can't possibly be a Muslim..."?
So for Pakistanis to celebrate the "Muslim invention of alcohol" rings awfully hollow: there's no inspiration for further accomplishment inside, no place to go, just an excuse to wallow in the glory of past ages while the path to free thought and further modernity is rapidly being bulldozed by the likes of the Taliban and the glorification of nuclear-armed militarism.