Not a paradox. It plagiarizes because it isn't capable of creating thoughts. It creates statistically likely combinations of tokens. Those "statistically likely" models were made by stealing a whole bunch of information.

The model hallucinates because it doesn't actually know what any of the tokens mean, just that they exist in a likely probability space.

If you took two papers about a very similar subject, copied them both out in their entirety, then replaced similar phrases from one copy into the other, the resultant paper would both contain inaccuracies and would be plagiarism. That's the same thing ai does, except the copies are the sum total of the digitized human written work. Increasing the number of sources you're plagiarizing from doesn't magically make it not plagiarism!