For Falcon 9, the costs and payloads aren't just claims. You can go to SpaceX today and buy a flight. For Starship, it's an in-development rocket with a focus

For Falcon 9, the costs and payloads aren't just claims. You can go to SpaceX today and buy a flight. For Starship, it's an in-development rocket with a focus on novel technology as well as cost engineering. Orders of magnitude cheaper is a great goal but it's impossible to know if or when SpaceX can achieve it.