FACT 2: Any couple has the right to kiss on a plane or anywhere else they wish.
But....what is kissing??? A peck on the lips or cheek should not be regarded as offensive. However, "snogging" in public, or holding a partner's buttock (as frequently displayed publicly by Hollywood couples) can be deeply offensive whichever side you bat for!!!
I fail to see why Mr Potgeiter claimed discrimination. Had a straight couple been asked to stop and then paraded in front of the passengers questioning the crew's decision. you would have seen the same outcome!
.......Disobeying a lawful command is a criminal offence - period!