The problem with that is that they're directly contradicting themselves. The actual metaphor is a "Scotsman" from the other side of the planet that's never actually heard of Scotland.
The problem with that is that every ideology which includes more than one person, and probably most if not all that only include one person, will always, by necessity, include some inherent contradiction.
Does the fact that there are many contradictory beliefs in Christianity that Christians both singularly and plural can hold simultaneously mean that these people are not Christians?
Catholics believe that the Eucharist literally becomes the blood and flesh of Christ upon consumption. But there are passages in the Bible which can be interpreted such that this belief is sinful, according to the logic of the Bible.
Evangelical Protestants believe that idea to be heresy for this very reason, and find Catholics to be internally inconsistent and therefore doomed to damnation for eternity as a result.
Yet there are passages of the Bible which can be interpreted such that not believing the Eucharist literally becoming flesh and blood of Christ upon consumption is also sinful.
And Catholics, as a result, believe Evangelical Protestants are internally inconsistent and possibly doomed to damnation for eternity as a result.
From either point of view, the other side holds a position which is contradicted by their interpretations of the guiding theological texts they ascribe to, and thus they conclude that the other side is "Not a true Christian".
But to someone like me, a die hard anti-theist, its just all Abrahamism.
Do you see what I'm saying, Mik?