Could they? The Apollo program took 9 years from conception to landing the first person on the moon, and cost $257 billion adjusted for 2020 dollars ($25.4B at the time). For comparison, the Artemis program was budgeted for $86B [0], with less to spend due to NASA budget cuts. The SpaceX Artemis contract is "only" worth $2.9B. Finally, the Starship program has cost an estimated $5-8B so far [1].
Some conclusions / opinions: Starship so far is relatively cheap compared to the previous program that took Americans to the moon. Developing a moon capable rocket takes a long time, especially if they don't just copy the existing designs from 60 years ago. And a single purpose rocket will long-term be more expensive than a more generalised / reusable platform, but that's more capitalist objectives than political (e.g. beating the commies).
Some conclusions / opinions: Starship so far is relatively cheap compared to the previous program that took Americans to the moon. Developing a moon capable rocket takes a long time, especially if they don't just copy the existing designs from 60 years ago. And a single purpose rocket will long-term be more expensive than a more generalised / reusable platform, but that's more capitalist objectives than political (e.g. beating the commies).
[0] https://spacepolicyonline.com/news/nasa-ig-artemis-will-cost...
[1] https://en.wikipedia.org/wiki/SpaceX_Starship