From what I understand... sail boats [in general] travel some 60% of the time under power??
I would think that's only applied to coastal cruising? For example, I "sailed" from the Gulf Islands up to Prince Rupert, and that was only about 20% under sail due to the nature of the Inside Passage. Similarly going up the ICW was 100% under power. But those were very small percentages of our time on the boat as a whole.
Except for Inside Passage/ICW, I'd say the rest of the time we sailed about 98% of the time (we entered and departed anchorages under power).
One factor is that we really couldn't have motored 60% of the time. With 40 gallons of fuel onboard (so let's say 30 usable), it would have been impossible. In addition, motoring was noisy and much of the time we had to steer (the horror, but autopilot tended to break often). Under sail, blissful silence and no need to helm (wind vane).
Anyway, not trying to say my experience is going to change statistics. My guess is that your statistic is true,
but only for a certain percentage of sailboats (so if all sailboats were included, the percentage would be much smaller). Lots of sailboats are out sailing like we were, and many don't even have engines (think of all the Lasers, Snipes, or what-have-you).
That's one reason I'm interested in a Trawler. If I'm going to be motoring, I want to be on a motorboat. Motoring a sailboat is not that fun, whereas sailing one is lovely, IMO.