What makes you think the moon landings of 1960s/1970s were great achievements, but spaceflight today is not?
probably because we literally invented digital computers for the purposes of doing it. The amount of technical construction and mathematics knowledge required to design build and manufacture the hardware of that era is lost, the space shuttle is one of the most incredible technical achievements of the US to date.
SpaceX doesn’t even use large rocket engines because they’re hard to build and impractical, but we managed them perfectly fine in the 70s