“This is already wrong — it might work” disingenuous much?

The point of that proposed watermark is that it can be imperceptible to the human eye but perceptible by some algorithm or model nevertheless. It only adds value to the product, but perhaps not as much as it would take to implement.

I think in your comments though you entirely overlooked the fact that DALLE 2 has watermark implementation and it is in no way subtle, but it can be cropped out.