Well precisely... but those who have been known to indulge in a little bdsm are mostly reasonably informed...
It's yer Joe Public that really needs to be made aware of this latest round of half-baked rule-making. As pointed out - some of the images that could potentially be said to contravene this legislation would in no way, shape or form, be considered to be pornographic by the vast majority of people.
No offence TC, but lovely though your horned nipple may be, I don't classify an image of it as pornographic