Why is "plagiarism" "bad"?

Modern society seems to assume any work by a person is due to that person alone, and credits that person only. But we know that is not the case. Any work by an author is the culmination of a series of contributions, perhaps not to the work directly, but often to the author, giving them the proper background and environment to do the work. The author is simply one that built upon the aggregate knowledge in the world and added a small bit of their own ideas.

I think it is bad taste to pass another's work as your own, and I believe people should be economically compensated for creating art and generating ideas, but I do not believe people are entitled to claim any "ownership" of ideas. IMHO, it is grossly egoistic.

Sure, you can't claim ownership of ideas, but if you verbatim repeat other people's content as if it is your own, and are unable to attribute it to its original creator, is that not a bit shitty? That's what LLMs are doing