Why not? Australia won't win until there are players harder and more effective at the breakdown - from props to locks to flankers. I'd prefer someone like Pocock to Hooper.
Look where most turnovers are won in the game today. It's from dominant tackles and players getting isolated. Even players who arrive first to the ball are only successful if there is a really ineffective cleanout.
Games where players are given the leeway to compete at the breakdown like Pocock in the 2011 RWC quarter final are almost non-existant now.
As others have said, Hooper topped test rugby in 2013 for pilfers won. He's not as good as Pocock at it but he is good.
It seems ridiculous to look at a game where we got flogged and pick out one of our two best forwards and say he needs to be better at the breakdown. You don't win many turnovers when you're standing in the in goal lamenting the try your team just gave away.