I am left handed and tend to use my left when doing things manually, though I am ambidexterous towards this kind of thing if I am using something battery operated.
Somehow I doubt it. The reason I doubt it is that masturbation doesn’t exist! Nobody does it. Ever. Especially in those societies with a left hand taboo, as they tend to be conservative about such things.
I can see:
TOURIST: Why is the left hand considered unclean?
LOCAL: Because it is associated with toilet activities.
I can’t see:
TOURIST: Why is the left hand considered unclean?
LOCAL: Because we tug our Johnsons with it.