People are mad to realize something they thought was spiritual and purely human can be reduced to a mathematical algorithm and be generated by machines.
Some claim they’re mad that it’s because the training looked at art without permission to develop the algorithm (which everyone knows all artist do, making those people look like complete hypocrites), but that just sped it up. It would have happened eventually anyway, because the fact is, art is not spiritual or uniquely human, it’s patterns and shapes, which computers are great at.