> Let’s say the costs in 5 years do get as low as $15 per kilogram or about 2 orders of magnitude improvement in launch prices. That means a 200-ton payload Starship would cost $3,000 to launch. Do you honestly believe that? The world’s largest rocket cost a total of $3,000 to launch?

You have missed three zeroes in this calculation ;)

15 per kg for a 200-ton payload is about 3 million$. That seems achievable, given that propellant costs are about 1-1.5 million.