I think he's (was) a genius, yeah. Extremely good at whatever he was doing on the pitch, either creating, scoring, or something in between. Even today he's always been about the eye test for me - stats only confirmed what I always saw. Even at this age, his technique, anticipation, footwork, ability to ditch defenders off the ball easily, is easily on par if not better than most strikers out there. He's not as consistent today, surely. And the genius part is because he was definitely one of these players that would get you off your seat dozens and dozens of times throught the years. He was either erasing entire defenses on his own in Man United, pulling off extraordinary goals of all kinds, or showing an uncanny ability to be at his best at the most difficult times and games of the season, and he did it for at least an entire decade.
As for the WC being necessary for me or anyone - eh, it's an individual calculation for each of us, I suppose. Some people will never give in and will defend Ronaldo to death even after the WC. I don't think national cups matter that much when I'm personally ranking players. Messi was extraordinary for Argentina, and I've maintaned that well before he had won his WC. In my case the WC cemented Messi a bit on this special case, but also because I'm obviously a bit biased towards Cristiano. In the end, I have my individual calculation and views of both, but I'd rather maintain Ronaldo is my personal preference, while understanding Messi edged him a bit as a footballer. Football is to be a positive for my life, I'd never stop appreciating another player because I prefer someone else.
In the end I'm a fair guy. I've even found myself defending Messi against Ronaldo fans because even I don't see eye to eye with many of them.
I agree it's a silly affair. I think there should be a list of the greatest, and among those players, it's a personal preference between you, me, and each one of us.
Edit: This whole thing has a parallel with Federer, Nadal and Djokovic