The problem is that is never consistent. Ronaldo (Brazillian) won 2002 but he was literally injured throughout the entire season except for the World Cup. Cannavaro won 2006 for his display in the World Cup, yet Ronaldinho was clearly the better player, having just won the CL and league. Based on the important cup competitions, one would think that Kaka deserved 2007 because of his performance in the CL.
In any case,
Nedved should have won in 2003
Sneijder 2010
and Ronaldo 2018
So technically, it should be 6 - 5 to Ronaldo's favour.
Well sorry to disagree here
There are politics in it (though not all the time)
Ronaldo would have probably won last year should he stay at Real (despite that I think Modric deserved it)
Ronaldo the Brazilian won it though he wasnt that great
Cannavaro was simply amazing in 2006 both for club and country and deserved it.
Sneijder should indeed win it in 2010
As for this year - You cant compare numbers between a defender and a forward.. You look at overall impact and since Van Dijk signed for Liverpool they became amazingly better...
Van Dijk was the number one reason for their CL win and deserved to win
P.S I`d give it to Salah and Mane before Messi while Ronaldo did the same as Messi this past year + International football (won)