In my time on a ship we were always undermanned. All the development I've seen in new systems to replace those I worked on (arresting gear and catapults) focus heavily on reducing required manning. We never did busy work or work that was unnecessary when we were under way and flying aircraft. In port - yeah sometimes.
Most current sailors I talk to are overworked, training gets gundecked, following safety procedures and impede advancement - what's reworded is a "can do" approach that takes large risks.
I don't know anyone currently serving, in any command, who says they have too many people.
I was on a nuclear sub from 1996-1999, so it's possible that my observations are no longer valid or don't apply to surface ships. But I suspect that my assessment would be the same even today. I worked with enough surface sailors to see that the amount of bullshit work they did was comparable to ours, and they didn't have nearly the physical space limitations that a submarine does.
It's not so much that we were doing "unnecessary" work, but rather that many tasks which required a dedicated person were so trivial that any reasonably competent sailor could easily handle two or three of them at once, or the task could be even more reliably automated.
One quick example is the fathometer operator: When we were sailing in shallow or uncharted waters, a sailor had to spend hours doing absolutely nothing but watching the depth gauge so he could give a verbal warning if we were in danger of running aground. This is not a job that requires a person's full attention even in the most challenging undersea terrain.
To some extent it's necessary to break jobs down into simple repetitive tasks so that they can reliably be done in a high-stress environment, but the navy really took it to an extreme. The end result was the overwork and fatigue that others are referring to.
Possible explanation:
a navy ship runs on rotation of three watches, each in turn taking control of the ship for 8 hours. Thus a ship ought to have a crew of 3x the manpower needed to run it. So by "crewed with about 1.5X the number of sailors that were actually needed", GP means a very understaffed vessel.
