2 of the 3 Tests he started last year were against the All Blacks and in both those games, according to the guys on this forum anyway, he was the best Wallaby on the field. Even with 5 missed tackles. And it wasn't just GAGR. Almost every rugby journalist also rated him as the best Wallaby on the day.
I don't know if Michael Hooper has ever been rated as the best Wallaby on the park against the ABs on this forum but definitely not in the last 2 years or so. So you can think I'm grossly overstating his output but then so is everyone here who voted him twice as the GAGR Wallaby of the game in consecutive outings.
Historically, Hooper has started untold more games than Samu so, like Gill and McMahon before him, we will never know how good he might have been because regardless of how well he plays, he will never get a proper shot at being the starting 7.