You're right, most critics comes from Messi fans looking for an opportunity to criticize Ronaldo that's why they expect Al Nassr to never lose a match. He is not responsible for other players performance and when the losses it shouldn't be in him. Had it been he is not scoring goals then it is okay to criticize him but he is even scoring more than any player in the league that means he is playing his part for the team.
Definitely not far from the simple truth,they criticise him in everything he does and fail to acknowledge his importance and relevance. I could remember when he was still at Real Madrid, they said he won only 2 La Liga and and he wasn't the reason why the team won Champions League, they were so quick to forget that in every trophy he has ever won, he was the top scorer and no team can ever win any match without goals. They also forget that in all of that his the highest contributor in terms of goals + assists in his team. I really wonder what exactly they want from him.