I’m quoting the article where the photographer erased the stars from the frames:
> Much of the time was spent painstakingly erasing stars, to reveal the satellites.
These aren’t my words. It’s what the article says!
The final image appears to have a frame of stars added for effect, but they are dots rather than arcs because they’re from a single exposure. The satellite trails are a composite of all of the images, with the stars removed.
Do you understand how composite images work and why they are used?