SpaceX is standing on the shoulders of giants.
But then Musk took over and once again a brilliant, innovative engineer was in charge, and so we are back to making real progress in space travel.
By the way, I am not talking about the space probe designers. They have been brilliant, and have produce an astounding series of scientific advances. But the rocket industry has stagnated.
Sure there are lots of brilliant engineers in the years after but these guys were not making top level decisions.
You can see that in all industries. MBA guys have kicked out engineers as leaders. I have seen the same while working in software engineering. Business thinking dominate over engineer thinking. You end up with these really short sighted decisions and there is an inflated fear of trying anything new.
Look at the SLS disaster: stuck on coupling together a whole bunch of old tech to the point that it creates its own complexity.
If a non-engineer is in charge of a space company, they'll look at the popular science articles and assume that single launch is the only way to do things. They'll also assume that we just need to get the material science right to be able to do space elevators. They'll assume that the only way to get into space is to get bigger and bigger space budgets. That will increase shareholder profits after all.
When you have an actual engineer running the company, they can question all those assumptions. They can take everything apart and put it back together again in different ways and question the assumptions of the "thought leaders" in the space.
In a way, this outside "thought leadership" by research institutes has hindered science by leading researchers given grants to carefully conserve and develop their pet solution to a problem that they are an authority on. If their idea falls out of favor, then they will lose their grant money. It's the extreme version of the innovator's dilemma. An entrepreneurial engineer just wants to get the job done. If they can't deliver a great product, they'll lose their revenue stream. If they can leapfrog the competition by capitalizing on their innovator's dilemma, then they'll move to true greatness.