According to this timeline, work on Apollo began long before Kennedy's declaration of going to the moon before 1970. The program evolved and mutated many times before the final configuration was set, but even then, it took years to develop and build. The rush also led to a fire that killed the Apollo 1 crew.

It's true that a good part of the time required to develop Apollo was due to the need to invent new technology. We wouldn't have to do so much of that for CEV. Avionics could be an evolutionary development of Shuttle systems. Life support systems are well understood. Electrical power systems are pretty straight forward engineering, as are thermal control, propulsion, attitude control and the like.

Other CEV parts will require substancial R&D ($$$). Software development is time consuming and expensive (see F/A-22 development). Heat shielding needs to be better than the Shuttle's, especially if the goal is to develop a vehicle capable of Earth orbital, lunar, and Mars missions (the Lockheed-Martin CEV proposal looks better in that regard). I believe we'd need to do some of those expensive pile driver tests to validate the heat shield design.

NASA's unofficial motto during the 1960s was "waste anything but time." Adjusted for inflation, their budget was at least twice of what it is today. At the peak of the Apollo program, over 300,000 Americans (mostly contractors) were working to build the components. NASA's budget isn't going to get that kind of boost, so even a 2010 timeline is pretty compressed. Some things take time and money. Remember "Faster, better, cheaper"? Engineers pointed out that you can pick any two, but not all three and expect success.