Because the title of the post is

Can coding agents relicense open source ...

My response was no, because the output will always be in the public domain, which is the opposite of licensed.

However your reply asked a different question:

So you are agreeing using the LLM worked?

This is a different question, because it's asking not about the general case of "can a coding agent produce a clean-room reimplementation" but rather "did the chardet rewrite achieve the goals of the maintainer?"

It's clear from the information uncovered about the chardet rewrite that it cannot be considered a clean-room reimplementation, therefore there is an argument to be made of copyright infringement, regardless of whether anyone can own the copyright for it.

But the title of the article is asking whether the general case is possible. In that case, an agent reimplementing a project that does not appear in its own training data and whose prompts do not contain any copyrighted source code, could in theory produce a clean-room reimplementation from functional descriptions alone, that would not violate the copyright of the author of the original project.

However in that case, the rewrite would still not be licensable since nobody would own the copyright to it.

I hope that clears up the point I was making and why it's relevant to the post.