People love to talk about both players, even those who don't like soccer know both of them, in every part of the world hehe
In my humble opinion, talking only about the 2026 World Cup, the two players could participate, but not playing all the time and perhaps not even as starters
They could be the player with the most experience, to give morale to the team, to help the new players, to come on in the second half or play a few minutes, take free-kicks, penalties etc
And I've seen several teams that have used this tactic
That's my bet for both of them to go to the '26 World Cup
It is true when you say that one player cannot save a whole team, but the presence of that player can only influence more luck and more opportunities for the team. Also, if that player is a celebrity player, that is, a star player, it can also boost the morale of the whole club or the team in the pitch. So, that is the kind of motivation that Portugal will be needing from Cristiano Ronaldo in the next World Cup.
At the same time, I feel like Cristiano Ronaldo is one star in a million in Portugal. Unlike national teams like Brazil, Argentina, and others who have a couple of players that are performing extremely well and could form a tough first 11, we don't see that in Portugal. Therefore, there has always been Cristiano Ronaldo and others until the coming of Joao Felix and Pepe, who have also been doing their own best, in the midfield and the defense.
The Portugal national team manager has a lot of work to do by getting in more talented players that can make up a tough full squad ahead of the 2026 Football World Cup. Else, Cristiano Ronaldo, Joao Felix and Pepe wouldn't be enough to bring a trophy home for Portugal. And unlike before that Cristiano Ronaldo was much more in form and could deliver miraculously, that is not the case any longer as the player is now old and can only serve as a morale booster.
There is every likelihood that the next Football World Cup would be the last national appearance he will participate as a player, maybe as a coach subsequently. But I feel that would be the last he would play in his professional career on the national team.