Its nearest ground station bounced off nearest satellite, or some inter-satellite laser links to make some hops, then to the user. It's optimized to be shortest route, just like routers with the wired internet you're using now: if you stream a movie, that request goes to in a short path from the server to you. You streaming doesn't slow down someone in China, because the data never approaches any equipment in China. Same with Starlink. Their data never approaches any starlink satellites in the US. When they get the whole grid laser link working, then it might, but it will still approach being optimal, with ground stations used as needed.

Ground vs laser is a latency thing, more than a bandwidth thing. No need to stream Netflix with low latency.