Granted, it's based on the same literalist thinking that gives us a 6,000 year old planet
No, it is not based on literalist thinking. The 7000 years creative "day" is just as symbolic as a "time period of an undetermined length".
Regardless, deep age is falling apart for secularists from a number of different points of view across many different scientific disciplines. Deep time is contradicted by the new James Webb Space Telescope.
They were supposed to find an early universe with lots of Generation III star formation along with little to no galaxy formation.
They found the opposite - fully formed spiral galaxy formation as big as the Milky Way from the dawn of time :
"This was astounding — we're finding galaxy candidates as massive as our own galaxy when the universe was 3% of its current age."...
"It turns out we found something so unexpected it actually creates problems for science. It calls the whole picture of early galaxy formation into question."
It calls a lot more than early galaxy formation into question. If the sun, moon and stars were all created in one day, this evidence is predictable and exactly what a creationist would expect to find.
For secularists, the list of things that don't fit keeps growing:
Neither Dinosaur Soft Tissue, human footprints in Carboniferous sandstone, nor star/galaxy formation seem to be affected by the passage of deep time and directly contradict a secularist world-view.
Exactly how much evidence does it take to convince a secularist that his worldview doesn't fit the facts? Is there any amount? Is it all bananas?
“It’s bananas,” said Erica Nelson, an assistant professor of astrophysics at the University of Colorado, Boulder, and a co-author of the paper, in a statement that accompanied its release. “You just don’t expect the early universe to be able to organize itself that quickly. These galaxies should not have had time to form.”