Committing copyright infringement against software vendors was automatic and free before, when it involved merely copying files, maybe after cracking the copy protect. It was still illegal. What makes you think this time would be any different? The fact that an LLM did it? Whatever an LLM produces humans assume responsibility for.

When you copy a file, it's trivially simple to prove it's a copy and not an original work.

How can one prove that X is a copy when none of the source code match original? Clean room re-implementations are not illegal after all, if we go that way (yeah, yeah, I know about clean room argument).

While I personally do not think it would be different, but a lot of LLM folks are, and even some companies (rushing to blatantly clone and de-compile stuff). Kinda strange feeling sitting and looking around in the midst of it, y'know.