Why AI art is so controversial

I think it can be a very useful tool for artists, but it could never replace real art. Why? Because art it's not just about painting pretty things, it's about creating them both mentally and creatively. An AI it's uncapable of creating, it just works with whatever it's users asked them to use as a reference. 
If we have to consider AI images as art, then a printer could also be an artist as well? Because it is not really sapient, it can't create out of free will (neither has a will at all) and it only does the things it does because it was instructed to do so by a human. 
About the point how "human also take inspiration from other works and artists", the difference is that a human it's incapable of exactly replicate another artist's style without intrinsically adding their own style for a variety of reasons: different techniques, different levels of drawing experience, different movements when drawing, different ways of doing it... Even if you study that said artist for years, you will never be able to do things exactly like that person would. But an AI could, because although it has neither creativity nor the ability to create something by itself, it is capable of exceeding the parameters that prevent a human from replicating images with mathematical precision. Just like a printer does.