Edit: Let me clarify for you only. If God created a heat producing sun, a cooled and solid
earth, a middle aged man and woman, with built in language and intelligence, plants fully
grown, animals in adulthood and planets fully formed, in six days, why would he then create
the heavens and the stars (rest of the universe) as young? Follow the logical conclusio
It does not logically follow that, because God created things on Earth old in order to support life, he had to create EVERYTHING old. Why does a meteor floating out in the middle of space hundreds of light years away from human life have to have old age? And not just any old age - the age scienitsts predicted them to be based on theories about the formation of the solar system. They're not just any old age, they're the age they're supposed to be. If we found metoers that dated, say, 1,000 years old, or 10,000, or a million, or just 1.4 billion, or any random number, we wouldn't be able to explain why that is. But, instead...4.5 billion years.
So yeah, why would he do that? Why would he make things old that didn't need to be old in order for Earth to support life? The only reason to go to that length would be to give someoen who was studying the universe the impression that it was old when it really wasn't. Which would be deceptive.
Your argument also fails because the Earth and sun aren't as old as they NEED to be - they're much older. If you took a billion years of life off the sun, it would still be able to support life. So why age the sun well past the age it needs to be in order to support life if the only reason you're aging it is to support life?
Come to think of it, why does the asteroid belt exist at all if the universe was made instantly? In cosmology, the asteroid belt is a result of the process that scientists generally accept created the solar system. They're basically leftover junk. If the solar system was made instantly, why is that stuff even there?