Speed of design of airplanes.

Here's a question-- why does it take so much longer to design and
protoytpe a plane today? Between the JSF and F-22 literally decades
have gone by.
Now, granted, the JSF is orders of magnitude more complex then say
an F-4...but on the other hand, CAD/CAM tools exist that give design
and engineering staffs tools that are also orders of magnitude ahead
of what was possessed in the 1960's.
So, to the engineers in teh group, are we seeing a problem that is
basedin the designing of the planes, or the process used to create
that design, in the administrative and bueraucratic ways things are
done?