So you couldn't prove PIA got banned and now you came up with this weird explanation.
US FAA and EASA have pretty similar safety standards and PIA still operates freely across Europe, this had nothing to do with a ban. Aviation doesn't work the way you think it does. I know this, cause this is what I do.
Banning an Airline is not as easy as you think and PIA stopped operating to US just because of utterly poor management and now it wouldn't be easy to restart that route cause many airlines are looking for new slots to operate and flights to US are very profitable for most of the airlines across the world and they take up any available slot pretty quickly.