I don't agree. You are basically asking Ronaldo to play like Messi, or else he will not be as good, in your eyes. They are very different players with different attributes. Ronaldo has bags of pace, is strong, can shoot with either feet, is terrific in the air and can shoot from long distance. Neither of those attributes are particularly strong suites of Messi. I know people had him down as the fastest player in the world, but that's just rubbish.
Messi has close control, agility and body balance as his strongest attributes, along with his finishing, which is on par with Ronaldo's. Ronaldo is taller and doesn't have that low center of gravity that Messi has, doesn't turn as quickly and isn't as agile in tight corners as Messi is. Why should he try to emulate that when he wouldn't be as good as Messi at it?
Ronaldo plays in a much different set-up than Messi. It's about fast counter-attacking style, which i prefer. Messi is massively part of the tiki-taka style as he is very much the focal point for their play. Messi doesn't go on runs like Ronaldo does, or like Giggs did. Ronaldo can still dribble and entertain when he feels like it, but fact is that it is far less productive than simply run past them. Giggs did that and Nani did that at his best; it's awfully efficient, and for me it's a joy to watch when they know how to. However, Ronaldo is still more about flair than a player like Bale who is more or less all about kick and run whenever I see him - efficient, no doubt.
Ronaldo wouldn't be as good or entertaining to watch at Barcelona, but Messi would also struggle more in Ronaldo's position at RM, simply because he would see the ball less and would be forced to go past his player using pace, which isn't what he's about.
Different styles, and preference is very objective. In fact, I would say it's a little bit one-dimensional to say that one style is more pleasing to watch than the other.