“SpaceX’s IPO promised that Starlink would quickly jump from 10 million current subscribers to 300 million or more in very short order.”
Ten million to 300 million is a 30x jump, and the pitch deck treats it as a schedule. T-Mobile has 142.6 million subscribers after decades of buildout, spectrum fights and a merger. Satellite is good at covering places nobody wants to build towers. It is bad at a dense city on a Saturday night, which is where the subscribers actually are. That number exists to support the IPO, not to describe a plan.