While it's possible that these AI tools will leave some (certainly not all) artists without work, what I think is really going to happen is that artists will harness them to do new things that were simply impossible before, or to make their work easier. Technology rarely destroys jobs; it more frequently changes their nature. Just like how at some points animators needed to know how to use 3D tools when in previous decades they didn't, in the near future graphical artists will need to know how to use AI. It's possible that where there were previously two artists working there will then be only one, but such is life. Demand for art is finite.