One the contrary - the reason copyright is called that is because it started as the right to make copies. Since then it's been expanded to include more than just copies, such as distributing derivative works
But the act of distribution is key. If I wanted to, I could write whatever derivative works in my personal diary.
I also have the right to count the number of occurrences of the letter 'Q' in Harry Potter workout Rowling's permission. This I can also post my count online for other lovers of 'Q', because it's not derivative (it is 'derived', but 'derivative' is different - according to Wikipedia it means 'includes major copyrightable elements').
Or do more complex statistical analysis.
From Wikipedia, "a derivative work is an expressive creation that includes major copyrightable elements of a first, previously created original work".
You can probably can the output of an LLM 'derived', in the same way that if I counted the number of 'Q's in Harry Potter the result derived from Rowling's work.
But it's not 'derivative'.
Technically it's possible for an LLM to output a derivative work if you prompt it to do so. But most of its outputs aren't.