As an editor with a publication, if the content is clearly taken from elsewhere, the first thing I do is give them the benefit of the doubt and check if they were the original author. I do ask people to write at the bottom “originally posted on ….” I think that is helpful to not get flagged by Medium for plagiarised content.

When it’s quoting from elsewhere, it’s pretty obvious. You just have to read the article.

Whatever else, I don’t believe that treating authors with suspicion is a decent way to treat people or gain respect.