I really really doubt that. Dude would be 40+ years old and if he is still playing then it would be like 3.5 years playing in Saudi league, that doesn't really prepare you for World cup. Before this one he was at least member of United and he was seen as not wanted and all that which makes sense and happens but we still didn't know where he would play, he was last played at United before he went there.
When you are the striker for United, even if there are issues you are still the striker for Manchester United, that is as good as it gets for most players. Now? He is an unwanted player playing for money in Saudi league, basically puppet for the rich people there, doubt he can even play up until that point.
The only way Christiano Ronaldo will be at the next World Cup is if he does an ad like Pirlo did in this one.
There's no way Christiano Ronaldo will be at a competitive level after playing years in that league and at his age. He already wasn't very good in the last world cup to be honest, no way he's coming back.
I don't understand why you think so.
In 4 years, new great players and stars will come, who may be even better than Ronaldo and Messi and delight us with their games. It's a natural process that happens all the time and every next world cup is better and more interesting than the previous one.
When I watched Maradona at the 1986 World Cup, I thought it was the pinnacle of football and that it couldn't get any better, but I was wrong. It was the same with the great generation of Brazil in 2002, with the real Ronaldo and Ronaldinho. At every World Cup, a new football star appears, so it will be the same at the 2026 World Cup, don't worry.