Until now, Google has made it easy for itself. The long-standing controls for web search have been the way to control the content in Google’s AI features, both in training and in display.

It seems clear now that, internally at Google, this position will not be sustainable in the long run. Published internal Google documents as part of the competition proceedings show that discussions are underway about Google’s options, what would be advantageous, and how it intends to position itself.

What’s interesting here is that the “No Snippet” directive apparently affects more than just the display. This could also exclude the content from training. However, Google doesn’t want to publicly admit this.
The document even recommends making the changes to the public documentation secretly and without public announcement. It’s also noteworthy that Google has the ability to make very granular distinctions about what happens to content—but appears not to want to offer this.