Let’s focus on Adam for a sec. He was created as a man….so he was created old. Wheres the debate about God deceiving us with Adam. He had hair….it takes years to grow hair. The bones in his legs were long - takes years for bones to fully grow. Why did God create Adam old?
There is zero indication that Adam was created old, so that's your speculation. He did not have grey hair; he did not have scars wherein it appeared that he had long years of working in the garden getting scratched and injured sometimes. There is no indication whatsoever that God created Adam looking like he had existed for decades or centuries.
It is reasonable that God created Adam as a young man, say 20 years old or younger, maybe even 12 years old, although he was really less than one day old when he came alive, becoming "a living soul," because it says that God formed him from the dirt, not from an egg. God did not make him a zygote or embryo. So then, after the U became stable, God created man 6k years ago. Don't assume (as many do) that if someone says the U existed for B of yrs that they are evolutionists; that would be a wrong prejudice.
But comparing Adam created as a man with the U created as if it were B of yrs old is a case of "apples v. oranges." There is no indication that Adam appeared to have existed for a lifetime already when he was one day old, whereas the U actually does appear to have existed for B of years, given the evidence we see in the cosmos.
So then, how one interprets Gen 1 depends on some assumptions. If the apostle Paul could write that what is observed in creation shows the invisible attributes of God, then certainly a U which appears to be B of yrs old shows the eternal nature of God, would it not? Then, Gen. 1 would not be so literal as you think it is. Certainly "day" in that context means literal day, but it does not necessitate a meaning of a literal day from a scientific standpoint. "Day" in scripture has a host of meanings, depending on its context, even though it's the same word with the same basic definition.
The way Gen. 1 is structured is similar to ancient near east cosmology. So the point of it is not to give a science textbook on how God did it and when, but rather to tell all the pagan nations and polytheists of that time that there is one true God who created everything. Since this is the point of Gen. 1, then to try and make Gen. 1 a modern science textbook saying how God literally made everything would be a mistake.
If God made the U as it is instantaneously 6k yrs ago, then why does it appear to have existed for B of yrs with all the evidences we see indicating B of yrs of history? Adam had no history when he was created, since there is no indication of it in scripture or evidence elsewhere. But observing the U shows B of yrs of history. I think that if you want to claim a 6 literal day creation, you have the burden to prove your theory, which I don't think you can, because no one has been able to prove that yet from a modern scientific standpoint.