[lmkg]

Are you making the distinction that most MtG decks are not Turing-Complete? Is that what you mean by "specific and artificial construction?"

I think most people assumed that Turing-Completeness requires a specific and artificial construction, which is where the disconnected (and downvotes) are coming from. Especially for something wasn't previously believed to be a model of computation at all, much less a Turing-Complete one.