he scored much more than expected, that's very effective finishing. look at cr's position for a "bad" finisher. (and tell me with a straight face that xg tells a better story than actual goals or assists.)
CR7 was horrendous in the first half of 2017/18, IIRC even Paulinho had more goals than him mid-season. Of course he turned it around in the second half of the season.
Benzema actually had his best goalscoring seasons playing next to Ronaldo. Even then, you can literally go on Youtube and pick out compilation of clips where he was missing sitters upon sitters Ronaldo set up for him.
Well naturally in the absence of Ronaldo, he’ll need to fill some of that gargantuan void but that doesn’t mean that the Portuguese inhibited his game or suppressed his potential when they played together. Benzema very likely wouldn’t have amassed the trophy collection he currently has if he didn’t have Ronaldo by his side. The latter also shielded and covered him from criticism when he wasn’t playing well as people tended to focus on him less.