I think it’s in most cases about the adult wanting or trying to re live their high school years where they had no responsibility etc and the power they have over hormonally driven teen boys.
My experiences says if your lucky enough to have a cougar “attack” you, remain quiet....she’ll come back and maul you again. :)
You may be right about the power angle. I bet a big part of the thrill for these gals lays in ordering the young guys around.