Yeah I agree, there are "generations" of technology, and I think that people in the 60's looked at the progress of transportation tech from 1910 to 1960 and thought "at this pace we'll all be zipping around the solar system like it's nothing by the 2000s." It was not easy to form an intuition of why the first generation of space tech was going to hit physics-imposed limits that would "slow that progress."
To be fair we still made lots of progress with space tech after the 60's, and I think via SpaceX and others we are hopefully now starting a new S-curve unlocked by cheaper access to LEO.
60s space tech also hit a lot of limitations of computers of the time. SpaceX's Super Heavy is in some ways a reimagining of N1's first stage, but with control software that makes it viable to deal with engine failures in flight.
But a big problem is also that the progress in space tech wasn't organic. There was no economic incentive, it was driven purely by propaganda, national pride and political goals. Once that fell away it took half a century for economic usecases catch up to a point where private investment was viable.
An interesting thing to think about was people used to think of getting somewhere. Now we think of things coming to us. In a way, we did achieve the "zipping around", it's just that we did it via the internet and wireless communication. Of course, it is not the same, but it is similar.
To be fair we still made lots of progress with space tech after the 60's, and I think via SpaceX and others we are hopefully now starting a new S-curve unlocked by cheaper access to LEO.