Starlink is nothing that you deploy and then you are done. When you have launched the last satellite, then the first ones launched will have reached the end of their lifespan and you essentially have to start over, deploy the entire constellation once again as the satellites reach the end of their lifespan one by one. With a lifespan of say 5 years, you will have to deploy the entire constellation once every 5 years, with 12k satellites you are looking at replacing 200 satellites each month, forever. That sounds possible without Starship but I can also imagine that being able to use Starship is necessary for the economical viability in the long run.