Check out this post from the ASTD blog called, Let's stop making excuses like, "our older workers wil not embrace learning new technologies." I agree that some are too quick to give up on people and make judgments about what's possible. Most of the professionals I know are learners - it might be deep down inside, but it's there.
This posts challenge us all to make sure that WE are not the real barrier. Because having a mature workforce is not likely the most pressing challenge to creating a hip and sage workplace.