That is not the dynamic with LLM. You see LLM output, but original creator is hidden. And if you write your own, no one will find it. Worst, other people will tell you "LLM could have write it" in reaction ... so people wont bother.
> search engines copied and indexed web pages
Notably, search engines sent people toward web pages. And when search engines stopped doing that and started to copy content, those original pages started to die out.
> Printing presses copied manuscripts
Printing press made dissemination easier. It is an equivalent of early internet, not of LLM.
> open-source software was incorporated into commercial products
Commercial product using open source library had different user then the library it is using. And crucially, it is not hiding that library from the library user.
> Wikipedia repackaged knowledge produced elsewhere
Yes, and we collectively create less encyclopedias. They are not worth writing and checking for correctness anymore, so we don't do that all that much anymore.