One of the things that allowed Frontier on Amiga to have 100,000,000 celestial objects possible in a single 770K executable file was the ability to have all but the nearest objects generated from an algorithm that approximated the "design" of the galaxy.
Because this mapping effort will only increase the accuracy of our already existing measurements and should not fundamentally change the algorithm for generating those distant star systems, it would only increase the workload on the team by effectively requiring hand-coding minor "tweaks" for billions of stars.
I like the fact that the galaxy is function generated and takes artistic liberties for the sake of efficiency. It was fun to think they could fit an entire galaxy into that single file WITH all of those splined ship and station designs, cities, missions, economic models, spaceflight models, geologic models (mining), administration rules (laws and police), combat artificial intelligence, and music!
It does sound like an interesting idea to include that data, but I prefer they take the already great data they have and employ it in the most efficient way possible so they can focus on features that make the universe "alive" rather than "accurate".