Thats wrong - NASA was NEVER really highest-tech, highest complexity. Even the SSME is not the ultimative perfect solution. It is very complex, but it has to achieve the then-impossible - after the design specs changed a lot. But as I will explain below, it is not the spearhead of human rocket engine design and not even the best what the USA had been doing in the 70s.
The Shuttle itself had been in many places a very conservative design, despite being the first space plane. It had enough experimental stuff in it by design.
Same that the Russians always use low-tech: Their engines are far beyond even the SSME. They use still metallurgy, that is nearly magical for us westerners (Does not corrode or burn in the presence of hot oxygen gas), operate at pressures, that are unreached by contemporary western engines, need no large pressure oscillation damper systems in their piping designs and are still cheaper than everything western (Because they have the skills to achieve with few carefully designed parts, what we can only do with many complex work-arounds). Compared to a russian engine, even the Merlin engines of SpaceX are primitive and expensive at the same time. They are maybe cheap for an US engine. But thats not the reference.
And had been using very advanced technology in their rockets and spacecraft. That they used the same technology then for decades by economic constraints is not intentional. And if you look at the last Soyuz launch, with just 6 hours to docking, you can see, what innovation really means.
That is what I mean with "The Falcon 9 even lets the R-7 look like high-tech". It is based on very old technology, that has low technological risk. It is by economics a conservative choice, but no innovation. It does nothing new, it simply does what we have always done (And thus, lets us be, what we have always been. Groundhogs). In a time, where spaceflight is stuck in doing, what we have always done, not uncommon. But nothing to celebrate.
Elon Musk seems to be trying to invoke emotions with his company, that NASA has left behind with the Shuttle - but when it is about paying bills, they are icecold and heartless, dominated by accountants, not engineers. Opposite of NASA, which is dominated by engineers, who have to please accountants, resulting in great solutions getting funded and thrown away.
