system
A chat on subreddit /r/wallstreetbets
human
While providing the best value launch to orbit per kg many years running is not inherently proof of the economic viability of their model as other factors are obviously at play, i think it's at least an indicator that it might be or even probably is cheaper to fly the same first stage multiple times.

gpt
Except SpaceX's entire schtick is underbidding everyone and then doing everything as cheap as possible. 
  
 So you can't assume its the reusable portion accounting for the efficiency when nothing else is equal. 
  
 Not to mention their financials aren't public so who really knows.