#3 Juventus and Ronaldo's primary focus would be on the Champions League

For all of Juventus dominance domestically, they have found continental success extremely difficult to come by, and have not lifted Europe's premier club competition since 1997 when they defeated Borussia Dortmund in the final.
In that time, they have been losing finalists on four occasions, including in 2017 where a Ronaldo brace was enough to sink them in a 4-1 defeat at the Millennium Stadium in Cardiff.
Indeed, Juventus have first-hand knowledge of Ronaldo's Champions League prowess, as they have been on the receiving end of his scoring boots on no less than 10 occasions, which is the highest he has scored against any team in the competition, including a hattrick at the Juventus stadium in the quarter-final last season which led to Ronaldo receiving a standing ovation at an opposing ground for the first time in his career, and played a role in convincing him to join the club.
Ronaldo has been almost superhuman in the Champions League, and his stats in the competition beggar belief. It is for this reason that Juventus shelled out such a huge amount to get him, and with both the club and his priorities set on conquering Europe, Ronaldo's league performance would undoubtedly be on the back burner.