No shit Rooney was shining alongside CR7 at Man United. Early CR was a different beast and player altogether compared to his Madrid career post-2011. He was a pure winger with increasingly voluminious G+A output. Even then, Rooney was also a second striker and never got more than 16 league goals while he played with Ronaldo. In fact, most goals he scored while playing with CR was just 23 in all competitions.
Of course Benzema and other RM strikers had to accomodate their game to account for CR's movement to create space for him in the box and regularly drifted to the left wing. And yes, Benzema had lots of spells of poor goalscoring form. Both can be true, you are pushing a false dichotomy.
[MARCA] Benzema: "We no longer bother to look at what a guy does on pitch, just who scores. And the next day, we consider him the best. It's happened to me: I play a bad game, I score and they see me as the best. It has become a sport where you look at the statistics only. I don't really like it."