Which core areas does NASA excel in, distinct from SpaceX's focus on transportation and infrastructure build-out?

Exploration, science, and stewardship of the international domain.

The text specifies that while private entities like SpaceX are leading in metrics related to launch statistics, cadence, and infrastructure, NASA’s mandate is fundamentally different and broader. NASA’s core responsibilities center on pure scientific discovery, which includes operating complex scientific assets like flagship observatories (such as the James Webb Space Telescope) and executing difficult planetary science missions, particularly those that explore regions like the outer solar system where there is no immediate commercial return. Furthermore, NASA handles the stewardship of international agreements and operations, such as maintaining leadership regarding the International Space Station.