The short explanation for NASA’s drive to help get commercially-backed space stations into orbit is two big “-ics”: Optics and economics. With the ISS destined to re-enter Earth’s atmosphere the quick and fire-y way in 2031 (originally planned for 2024 but it was given an extension) due to a combination of wearing down from age and newer more effective equipment becoming available in the decades since its initial launch, the agency wants to make sure the U.S. can maintain a presence in space.
Beyond wanting to keep that previously established foothold, it also wants to help establish “a thriving space economy” – and farming out funds to promising commercial companies like Blue Origin and Starlab is how it plans to get the job done. These commercial space stations would then, in theory, act as their own surrogate versions of the ISS (with updated technologies) and offer services to both governments and private sectors for continued scientific tests in microgravity, as well as what could best be described as space tourism.
However, some of these commercial entities have begun to back out of the project for various reasons, meaning NASA has to start from square one in at least a couple of different projects with less time to finalize everything before that 2031 cutoff — and 2031 isn’t very far off in terms of developing and implementing a working orbital space station.