I think when you go into a discussion of people adapting game mechanics to other uses and start using "plagiarism" you've made a categorical error right out the gate, and it'll lead to nothing but more of the same.
You may be correct. I am new to forums and this particular scene. The sharing of mechanics is a totally new and somewhat strange practice to me. Though after my research it seems to be normalized. I will point out the technical term for this is derivative works. When concerning subject matters that can be copyrighted, what people are doing, adapting, plagiarism, derivative works....what ever you want to call it would be not be legal when concerning copyrighted material. And while I see the value in this medium not being copyrightable, I still consider the moral aspect of what is being done.
My earlier point when comparing to AI, is that people stand on the moral high ground talking about stealing other people's work. However, talking game mechanics and suddenly that morality disappears, not so much as the action has changed, ( with exceptions of course), but the context of when the " borrowing of ideas" takes place has changed. I am asking for the grounds on people maintain, which appear to be somewhat hypocritical in nature.
My original point cited a person literally quoting another systems work, and how they were going to use it in their own work. There was no permission, nor compensation. Giving another person credit, quite often, does not pay their bills. If people are offended that I might be suggesting that "they" are guilty of such things, it may be best that they ask themselves, am I accusing them, or are they feeling guilty and unnaturally defensive as a result?
One point that was brought up, was whether or not I have dragons, HP and roll dice. I think it fair to add that in order to have a genre, there will be some commonalities. After which there will be personal expressions. Genre is defined as follows, A genre is a category of artistic, musical, or literary composition characterized by a particular style, form, or content. So in answer I am part of the genre, so therefore there will be elements that will be familiar, others that break away from even this genre conventional thinking.
My question more over is if we object to AI taking the ideas of others, Why do we not question doing so, so directly in this genre? If morals are our basis, then why abandon them here?