You say that but Santos started Ronaldo for all the group games and only seemingly dropped him from the R16 game because of the reaction to being subbed, rather than because he was rubbish. Maybe there was a bit of both in there, and maybe some of the Portuguese posters can enlighten us, but I get the impression if there wasn't such a strop in the South Korea game then he may well have started again vs. Switzerland.
Agree with Lucas he still has a role. Whatever you think of him as a person, he still scores a lot of goals and there aren't many better genuine strikers at this tournament, You bring him off the bench with the game tied, or with Portugal losing, and he will command the attention of defenders regardless of his age. They're not going to be ignoring Ronaldo when he's loitering near their penalty area.