They know how it looked 4.6 billion years ago because they can do the math. So can you! And there WAS somebody there (here) to see it, for instance anybody who looked at the picture above.
For instance if you’re on an ILS, on final, and crossing the outer marker at 5 miles. Assuming it’s VFR conditions so you can see the end of the runway, and knowing that light travels at about 186,000 miles per second, when you cross the outer marker, the light from the end of the runway needed 0.0000269 seconds to reach your eyes. So in that case you are seeing the runway as it looked 0.0000269 seconds ago.
Or if you look at the moon, you’re seeing it as it looked about 1.3 seconds ago. I’m going to assume you can follow along here. So instead of being 0.0000269 seconds away like the runway on a 5 mile final, SMACS 0723 is a bit further out, so it takes 4.6 billion years for the light to get here.
Pretty simple math, even for a pilot. No need for bible passages, or sarcasm, just second grade multiplication and division.