Why AI art is so controversial

Personally, I think no one has the right to be mad or offended. We wouldn't have had cars today if we said "But what about the horses?". We wouldn't have had cameras if we said "What about the painters?". We wouldn't have had cotton candy machines at home if we said "What about the cotton candy sellers?". Humans constantly seek what's more efficient and as long as this development isn't ethically wrong, it should be fine. As long as the A.I. isn't stealing, but only using artworks it could use, I think it's fine. As someone who likes drawing in their free time (not really an artist though), I was never offended by A.I. art but amazed and inspired by it, just like I am by an artist's work, and that's not a bad thing. Many people who are offended forget that behind the A.I. is a talented and hard-working programmer too.