I don't think Ronaldo will ever become a coach. He would be rather the guy who owns part of the club or become the president and do more things in the background. His lifestyle and all the entrepreneurial projects he has make it unlikely that he would work as a full-time coach. Of course nobody can know it for sure, but I doubt he is the kind of guy who would want to work 365 days a year as a coach.
There is also this wrong idea that every great player can be a great coach. Look at Maradona, he was so bad as a coach. Ronaldo has all the top qualities as a player, knows where and when to run and how to execute everything on the field. But I don't think he is a strategy guy like Guardiola. He is also not like Zidane or Ancelotti.
President is more what resembles him. He could boss around a bit and he wouldn't have to be dealing with daily issues like a coach has to.
I think I totally agree with you, mere looking at Ronaldo I don't see him as a coach and so far I still haven't listened to any of his interviews were he said anything like being a coach after his footballing career. I see him as a leader but not from the stance but from the backroom, like you said, something like a club owner or a president of a prestigious club. That role suits him well, where his able to call the soots that happens in the club. That's the role that I see in him and not a coach like person. But like you said, it's still uncertain as to if he will be a coach or not.