A publishers entire value add is curation of content for their readers, and possibly increased exposure/recognition for writers. AI generated content has skewed their costs of providing their base service. They either need to find a way to make their curation/review cheaper, or pass on the costs to either the readers/writers.
If we find ourselves in a world with infinite mediocre content, we'll see the true value people place on content curation, in the amount that they can charge the consumer.