I'll just be extremely candid: a lot of people don't give a shit about these art pieces or art in general. It's okay if you do, there is nothing wrong with that, but it's a myopic view that the world would be worse off if we didn't have a portrait of Mona Lisa.
That's not the point, but okay. I'm simply pointing out the fact that there'd still be art, just not those pieces created by those specific people and the world would be just fine. Humanity would've fared okay if Nano Banana was created 500 years ago.