Comment by sva_

I think this paper is more focused on figuring out what would happen in the theoretical scenario that most data on the web in the future might be AI generated without being marked as such. As they say,

> We find that indiscriminate use of model-generated content in training causes irreversible defects in the resulting models, in which tails of the original content distribution disappear.

The companies you listed are surely not training the models indiscriminately. In particular they have piles of data for which they can have high confidence that they are written by humans.