Everyone has noted that the bottom line of the report is that NASA doesn't have enough money to both go beyond low Earth orbit (LEO) and continue the other politically mandated missions. But it's worth noting a couple other aspects of the summary: From the very beginning of the document, there are two disturbing statements. First: "Human safety can never be absolutely assured, but throughout this report, it is treated as a sine qua non. It is not discussed in extensive detail because any concepts falling short in human safety have simply been eliminated from consideration." Second, in its list of fundamental questions: "On what should the next heavy-lift launch vehicle be based?" Both of these statements (though more subtly in the case of the second) are about risk, and NASA's costly and extreme aversion to it ever since Apollo. Recall the famous words of Gene Kranz (that he never actually said, despite the fact that he used it as a title for his autobiography) from the movie Apollo 13: "Failure is not an option." The problem with that is, as some have responded, that success gets very expensive. This is the cost of risk aversion.
It does seem that the early, less risk-averse NASA accomplished a lot more. But can our political system today tolerate things that don't work the first time?
C for yourself.