This argument is imbalanced. Not necessarily wrong.

To follow scientific method, you should specify what would be meaningful according to your parameters: not merely parroting. If and when that is achieved by LLMs, instead of moving the goalposts, accept that something genuine has happened.

>> We will be flooded with content that will get harder and harder to prove wrong, but it will be wrong.

I mostly agree, especially about quantity. But since you wish to draw a line in the sand, define quality. Or truth.