He's making a point about responsibility/liability.
If you only get copyright for the prompt you make, but not the output, then it's like being responsible only for the prompt, but not the output.
Ie he's only responsible for pushing the boulder up the hill. The fact that it rolled down from the hill and crushed someone's house "isn't his fault" (he doesn't get copyright on it).
alt Hacker News
He's making a point about responsibility/liability.
If you only get copyright for the prompt you make, but not the output, then it's like being responsible only for the prompt, but not the output.
Ie he's only responsible for pushing the boulder up the hill. The fact that it rolled down from the hill and crushed someone's house "isn't his fault" (he doesn't get copyright on it).