From what I can tell that's 27% of the _game systems_. Then they have the actual rest of the game to build with all the actual content. Planets, scenarios, dialogue, story (if there is one) etc.
Which is frankly MIA most of the time, Squadron 42.
The game content actually seems pretty quick to produce, given that it's been highly automated. They went from next to nothing to 20+ planets/moons with a mix of procedural and hand placed locations to visit in a short time frame. The technology means the artists basically paint the planets content in real time with brushes. Then the missions/social content is also a mix of hand written and procedurally generated content, eventually backed by an economic model that fuels the missions and NPC behavior. This all makes sense because it's an infinite open world, not a story game, but so far it plays pretty well.
The "hero" landing zones seem to take the longest. My guess is they will launch with only a handful of the star systems and build from there.
Oh, and also another game (Squadron 42).