I blame the "space race" narrative - it made everything unsustainably expensive just to beat the goal of landing on the Moon by the end of the decade and before the Soviets. That also made the program even more dependant on political whims and easy target for budget cuts in the Vietnam era.

I recommend looking into the space flight plans from the pre Apollo - while tere were bonkers ideas like Project Horizon, most of the plans sounded quite sensible, with incremental building of space infrastructure and emphasis on cost and reusability (in the 1960s).

Of course when it became a race all the sustainability and infrastructure went out of the window and got sacrificed in the name of speed. :P