AI is far more productive, and easier in modifying source pictures, than photography. Controlnet is not a mere tint, it can generate 20 artstyle variations of the source image in 30 seconds. No artist will have any income if this those AI outputs are copyrightable without cost.
I don't think past-decisions are that important here. There'll definitely be new laws around AI generated content, that set clear standards. Those standards have to consider the social impact of copyright and the livelihood of artists. The whole point of copyright is not some abstract golden moral standard, but something that keeps artists and writers employed.
That's why I think pay-for-copyright is the best balance in terms of liberty for AI art but preserving the incomes of traditional artists.