Cristiano Ronaldo may play for his country in this World Cup but I have never seen another player as old as him. The speed that Cristiano Ronaldo has and the style of play and scoring goals are completely different from other players. The way he is still playing football is like a young man but he can play like this for a long time but due to the age barrier he may retire after the next World Cup.
However, the most likely thing is to serve as a coach for the Saudi League, if he serves as a coach for the Al Nassr team then Al Nassr will definitely get another reasonable and experienced coach.
That is the most obvious thing about him, even at his age he is still decent. The trouble however is that, even if a 40 year old Ronaldo could be better than some 25 year, hell even most 25 year olds, the reality is that he is not as good as he used to be. This is the issue, he is not getting comparison to other players, he is getting comparison to his old self and because he was such a magnificent player, he is not as good as he used to be. That prevents people seeing him be that great, and that is why he is getting judged.
You can't expect someone to be awesome forever, you just have to look at others and see if he is still worth being like this. Obviously PR and marketing is another whole reason why they are paying him so much, that part is of course true.