Dribbling is actually running with the ball past your opponent. Hence, dribbling and passing are the two most fundamental parts of the game. Even the defender need to be good in these fundamental aspects.
It's true that Ronaldo is very good at what he does i.e. scoring. But the problem is he is good only at that particular aspect. Apart from the 1 or 2 total amount of minutes Ronaldo have the ball near the goal, he is basically a one player minus in the team. That's the team is constantly building up play with 10 players for the entire 90 minutes. And that's why when Ronaldo doesn't play Real Madrid are actually better in the build up and they could create chances systematically more.
Hence, apart from the marketability and Sponsorships Real Madrid gets, Cristiano is negatively impacting the team.
If you look at the greatest forwards of all time one of their strongest aspects would certainly be Dribbling. Be Maradona, Pele, Cruyff, Best, Di Stefano.
You might be a great player with strong passing and positional abilities if you're a midfielder. But for a forward, you need to dribble. Otherwise you can't participate in the build up play which seriously degrades the overall efficiency of the team play.