It is a hybrid approach.

It’s primarily hundreds of hours of hand crafted content that’s seamlessly integrated into a procedurally generated landscape.

So for example there might be a mine colony gone wrong after a disaster.

If you have been mostly interested in playing on desert planets that facility might be loaded into the desert planet. If someone else has been focused on arctic planets, it might be on their arctic planet.

The same handcrafted content, but dynamically integrated into the spaces that each player naturally gravitates to in their own open universe.

This also makes the modern behavior of using a wiki to guide play much more complicated, and encourages self-driven discovery rather than community driven guides.

I think people worried about procedural generation because of how it was done a decade ago might be in for a significant surprise.