If you are going to create a planet (or universe) from scratch to be the home of an intelligent species, including a realistic history is critical to give that species sufficient historical context to learn about how things work.
Understanding evolution and biology is a lot harder if you have no fossil record. Understanding plate tectonics is a lot harder if you don't have a consitent geologix record. Understanding physics is a lot harder if you don't have a light coming in from events that predates the creation of the universe.
Thus if you grant that the universe was created 7000 years ago with a huge, detailed and consistent history, the clear implication to me is that we are intended to study that history to understand the universe in which we exist.
Went into a creationist museum once (real thing). And the literal answer to your question was ”Yes, Satan put the fossils there to temp us away”.
I can’t attribute that to all creationist, but it was the case for the few I interacted with.
He changed the subject and never brought it back up to me again.
Why did the deity put the fossils there? In order to confuse us? In order to challenge the faithful? It defies reason. You can only put it as a mystery of faith. But it needn't be.