Old Earth Creationism and similar views are a blight on the Christian faith. Though it is entirely possible to be a Christian and an Old Earth Creationist, such a contradiction is unsustainable. The doctrine of Creation is one of the most basic doctrines in the entire faith, so much so that even an educated atheist may be able to understand it. The "young" earth interpretation is not only obvious from the text, but is also the dominant view throughout all of history.
So why do Old Earth Creationists exist? There are two main reasons: A deficiency of faith, and/or a deficiency of education. To give an example, I will share an extract from an article an OEC recently shared with me regarding the pre-Adamic human hypothesis:
"Many traditional Christians – and their leaders and institutions – are threatened by discussion about people who lived before Adam because it could disrupt some long-held church doctrines:
✦ Age of earth and six-day creation
✦ Perfect world, and no death, before Adam's sin
✦ Original sin (every human born guilty because of Adam's sin)
However, the issue can no longer be ignored in light of all that archaeology has uncovered in the past fifty years. The evidence is now overwhelming that there was human activity on earth long before 4000 BC."
This kind of statement is actually very typical. You will find many such statements in OEC arguments. Note the confessions. First, it admits that the doctrine of Creation is a "long held" Church doctrine. Indeed, it is very long held. Many authors long before Darwin, including Moses, Josephus, Origen, Augustine, Newton, and more, all believed the Earth was around as old as modern "Young" Earth Creationists. By contrast, while there were indeed cultures which professed old earth views, there is virtually no evidence that anyone in the Church ever fell for it. Up until around the 1700s, the Church seems to have been unanimous in their view that even 10,000 years would be too old.
There's a reason for that: The Bible is very clear on this issue. This particular extract does not admit that, but OECs do not often deny this. Indeed, the very phrase "taking Genesis literally" requires that the "young" earth view is what Genesis literally presents. The question is whether or not we should take it literally. That brings us to the second confession in the extract: There is a reason people don't take it literally, and it has nothing to do with the text itself.
The reason modern compromisers interpret Genesis the way they do isn't because any normal rule of interpretation would compel us to do so, but because of the modern narrative. Namely, "The evidence is now overwhelming that there was human activity on earth long before 4000 BC." Now, this is where an honest person would say "ok, then the Bible is wrong". My friends, I am a Christian, and I have faith that can move mountains, but I have no reservations about saying that if the evidence told me the Bible is wrong, I would just flat out admit that. If I continued to believe, I would not reinterpret Scripture, I would simply admit Scripture says X, the evidence currently says Y, I will hold out in the hope that eventually new evidence will show that X is correct.
This is actually nothing new. My go to example is the Hittites. For quite some time, the only extant source describing the Hittites was the Bible. The rest of the evidence did not fit. There was no extrabiblical evidence of the Hittites. However, Christians remained faithful, and in 1903, the Hittite capital city was discovered, and now, we know the Bible was right the whole time, and the evidence was wrong.
Why is Evolution and the like any different? I strongly disagree that the evidence is overwhelming, but let's suppose it was. Would it be right to suggest we reinterpret the Bible? No! That would actually be very dishonest, but on top of that, it would put us in a very precarious position. Namely, the Bible would become completely useless. See, if we interpret the Bible in light of our current opinions, it ceases to be of any value. It may as well be a notebook or diary for us to write "I believe this", only for us to later scribble that out and write "actually, now I believe this". By contrast, if the Bible is the infallible word of the Living God, not even current academic understanding should be allowed to interpret it for us. Rather, we should use it to interpret current academic understanding.
Ultimately, Old Earth Creationism is a completely unsustainable position. If the Bible is true:
✦ The heavens and the earth were created in 6 days, about 6,000 years ago
✦ Adam was created on the 6th day, as was Eve
✦ All humans are descended from both of them
✦ There was a literal, worldwide flood
✦ There was a real place called Babel from which the human race was separated into various people groups by the confusion of their language
If you are an educated Christian, you know that. If you are a faithful Christian, you believe that. The only way to be a faithful Christian and an Old Earth Creationist is to not know that. The only way to be an educated Christian and an Old Earth Creationist is if you have some faith placed in some unGodly idol. If you are an educated Christian, with a faith solely grounded in God's word, it is 100% impossible to be an Old Earth Creationist.