I have an article running along similar lines in the works at the moment. I agree with you that SpaceX is now Starlink with a rocket company attached. Without Starlink, SpaceX would be launching far less often, and look far less profitable. The constellation is also close to being finished - Musk should roll out the initial 4000 satellites by next year. The 7000 V band satellites seem to be abandoned and the 30000 E band are still just an idea. So that would mean the launch rate for the Falcon 9 will fall off a cliff sometime next year, unless Musk fires off a bunch of useless satellites. Musk will also need to prove Starlink is viable as is - if he can't turn a profit with the 4000 satellites it will be tough to ever do so. Starlink v2 looks like more power, and perhaps it will be an excuse for Starship. But Musk only has room to put up a few hundred of these v2 satellites, so its hard to see them creating a huge demand for Starship. All in, I'd say Musk has two years to get Starship up. Any longer and things start to fall apart.