So early today, Deadpool fans were shocked and surprised by the news that director Tim Millar had decided to step down from directing the 2018 sequel for the Merc of the Mouth, as we knew is that he left over creative differences with Ryan Reynolds, but we had no details as to what it was, but now we know, The Wrap has revealed that it concerned the casting of a certain fan favorite time traveling mutant. This is what the site had to say regarding the topic.
"We’re told the director was all set to make the sequel, which still doesn’t even have a release date. That’s allegedly in part because when Reynolds’ agents renegotiated his deal, along with a massive amount of money, the star got casting approval and other creative controls. That whole process took more time than Miller (and fans) would have liked, and it shined a spotlight on differences in vision between the two key players.
Miller, who owns a visual effects studio and we’re told did much of the polishing work on the original “Deadpool” for free, wanted more of a stylized sequel, while the actor placed his focus more on the raunchy comedy style that earned the first movie its R rating.
The casting issue also eventually came to a head over the possible booking of Kyle Chandler in the sequel. Mashable movie reporter Jeff Sneider first reported Chandler’s potential involvement with the “Deadpool” sequel during a “Meet the Movie Press” podcast, saying that the actor’s name has been “floating around for Cable for months.” Allegedly, Miller wanted the “Bloodline” star to play Cable, though Reynolds did not. Ultimately, the studio backed its marketable star, and the man behind the camera packed up his lenses."
So basically since Ryan Reynolds has some creative control over the movie, he has an say over who should play Cable and he and Tim Miller didnt meet eye to eye on who should play Cable, so whoever ends up taking over the directing chair will have to see eye to eye with Reynolds over who should play Cable.