I'm just curious why is everyone talking about transformative nature and so little focus is given to: 4.the effect of the use upon the potential market for or

I'm just curious why is everyone talking about transformative nature and so little focus is given to: 4.the effect of the use upon the potential market for or value of the copyrighted work (wiki) I don't know if this particular case is good for exploring all angles of fair use, but to me this certainly is a greater hurdle for commercial generative ai.