I have also had the same thought, for me Portugal can reach very high if they propose it, from what I saw in the classification for the world cup, Portugal had a hard time reaching the world cup, they had to reach the repechage and that is a very difficult position for a team of this caliber, but of course by leaving behind teams like Italy and Sweden CR7 knows that this opportunity cannot be wasted and as everything is going, being his last World Cup he will do everything possible to win it and be one of the top scorers, the same for Messi, I think this World Cup promises to be one of the most exciting of all.
Cristiano Ronaldo is 37 years old already, it's already a bit on the older side to be at his best, so I don't think he's going to push Portugal to the finals. I think this world cup will be a bit of a surprise, new, younger people will be able to show their talent. The weather in Qatar is also not amazing so people will have a hard time playing there. It's going to be a young team the one that wins this one.