How did we get humans on the moon in 1969 and are still struggling to get the Starship rocket to launch properly?

In the early 70s it was a risky and expensive one-time deal. Starship is doing it sustainably and will completely revolutionize space travel. I wouldn't say they're struggling they're just still developing it.

The capabilities of starship are orders of magnitude more payload and for orders or magnitude less money at the same time.

Turns out it's a bad idea to totally scrap a billion dollar rocket every time you use it.