I would suppose it's possible that God made a universe that *looked* billions of years old when it really is a young universe.
But a look at mitochondrial DNA poses a problem. You see, Darwin's evolution is just a theory in some ways, but GENETIC evolution is a proven law. We can actually measure how many generations human beings are removed from each other. With a big enough computer and a concerted effort, we could create a family tree of every single human being.
On one hand, the results are fairly amazing: We are actually all descended from a single mother, not all that long ago! This discovery is so shocking, the universal mother was actually dubbed "EVE" by scientists. On the other hand, whereas the bible records about 70 generations (plus 2000 years), the data shows about 1000 generations: tantalizing close, but significantly and inescapably distant from biblical projections.
I do agree with you that the discussion of creation is not essential in regards to Salvation. The problem is the widespread perception that science is antithetical to Christianity. Some of us must hold the door open for the salvation of scientists, and to allow Christians to study science.
The continued existence of comets -- our knowledge of how terrestrial and extraterrestrial catastrophes are evolution stoppers hundreds of thousands of times, over billions of years -- lack of transitional fossils, lack of erosion characteristics in most geologic layers -- the pooling of fossilized bones from supposed disparate ages -- lack of long term silt in the oceans from continental erosion -- lack of sufficient dust on all known solar bodies -- continued high energy geologic activity on small planetary bodies that should be dead & frozen solid -- mature galaxies when they should still be in the developmental stage according to the big bang model and the general befuddlement by the scientific community at all of the continued contradictory data being revealed by modern technology.
Science is great for some things, but deceptive when it comes to theorizing where the data doesn't allow. 1000 generations of mDNA translates to 40,000 years, well within the potential genealogical gaps within the Scripture. I personally believe it is closer to 10,000 years and there are not gaps in the genealogies based on the only authentic revelation that has been supernaturally preserved by our Creator, the Holy Bible.