Oxford doesn't recognize the phrase "Sandwich Artist". You aren't abiding by the rules you hold others to. That's not even touching the fact that dictionaries do not define words; they record their usage. As such, they will always be out of date.
In short, everything you've said is completely wrong.
It's a phrase, which is something the Oxford dictionary acknowledges and defines. His use of scare quotes only excuses him if someone else had used that phrase before him; instead, he's the one who brought it up. It's quite obvious he wanted to use some predetermined meaning he had for it. Arguing otherwise comes off as useless pedantry.
I don't see what's so hard to understand about enko's point. Enko dislikes when people misuse the word 'optic'. Enko dislikes when people misuse the word 'artist'. Why in the world does it matter who brought it up?
Someone giving an example of something they don't like said doesn't make them a hypocrite for saying it, especially if they quote it. God sakes.
In short, everything you've said is completely wrong.