AS: this question seems to mix too many ideas into one soup. Would try to separate the concerns. So the question of ethics and self-esteem i offloaded to Appeal tag wiki rejection? Plagiarized - nothing?
Is there a standard way to appeal rejections, when they are made for bogus reasons ?
Matt Ball is entitled for his opinion (though i think that informative but informal description is anyway betetr than NULL). How it is said about questions - "enhance rather than close".
But two other decisions - This edit plagiarizes content from an external source without proper attribution - are nothing but insult that there seems no SO way to refute.
BTW, why at all this "plagiarism" insult is even possible to put without providing the source that allegedly was plagiarized?
It is interesting that some say like "the wiki page does not repeat the term" but the term is told in the excerpt that is always rendered together with main text. https://stackoverflow.com/tags/epsilon/info
Seems like separate review processes just make wiki need to copy-paste te excerpt once and again