certainly, if it is observed selfishly...but if "the other" thinks it feels good, what's wrong?
as a rule for individual behavior, more than inadequate...but with a more socially inclusive interpretation ? the golden rule should be "do unto others only as they would have you do unto them"...
of course there would be pigs who believed that a child really wanted to have sex with them, or other rationales, but at least the goal would make more sense...
and it's much easier and to the point than endless philosophizing about how much lubricant to put on an umbrella, or whether there is anyone else on the planet but you and yours, etc.
fs