What can generative AI do that can't be done, and done better, otherwise? Nothing.
It's not an attempt to replace or add an artistic medium; it's an attempt to replace the artist. It doesn't open new avenues of expression, and it has negative journalistic value too.
People who "make AI art" are not making art, nor making anything else. They are commissioning images/videos/text from a bot, just as people commission art from humans. The amount of praise/admiration this deserves is zero.
The unfortunate truth for art is that gen AI will stay, and they will take work from artists, just like photography did from painters. There will be a niche for it at some point, and until it finds that niche people will fight over it.