He'd never beat GSP, Fitch, Shields, Alves or Kos among others, so no.
His standup has not evolved with the sport, and he's getting old. Sure he can sub guys like Almeida but his striking against Serra and Gracie was embarrasing.
Yeah in order to get to a title shot, Hughes would need to get past one of the top four gatekeepers to the title before he actually faced GSP and they all are at their elite levels. While nothing is impossible it would be extremely difficult for Hughes to make his way to GSP!