Realism Necessary for Art

People are confused about art, or if not confused, willfully ignorant. You see people trying to be edgy or avant-garde by looking at garbage and calling it art. I don't mean art that is bad in technical skill (like a child's finger painting) or even immoral (I'll use my better judgment and not cite anything here), but literally a thing that doesn't belong to the category of art but that some people want to claim it is. What art actually is, I won't explore in depth here, but I do want to say that realism is a necessary condition for something being art. 

I have to be careful about the word "realism" because that's somewhat technical in the art world.  By realism I mean that whatever the subject is in the artwork, it has to capture (or at least attempt to capture) the essence of the thing. And this presupposes that things have real knowable essences. So I mean metaphysical real essentialism. The image must be trying to take a form, something like a Platonic form, and have it meet physical reality, much like Aristotleans understand the world, mostly compositions of form and matter. So, if the "art" subject does  not even attempt to capture a form or essence of a thing (be it directly like my current heading of DaVinci's Virgen of the Rocks or indirectly like Impressionism) it cannot be considered art. Some clear examples of this are Jackson Pollock and Mark Rothko. 

Again this is not to say all art pieces that capture a form of a thing is art, but that it is a necessary condition for it. If it doesn't have it, it isn't art. 

So, if we look at the Virgen of the Rocks, which no sane person would deny is art, and compare it to Pollock's...um...splatterings, in order to consider the latter art, we should be able to find something which they both have in common to merit Pollock the title art. It is clear that apart from the use of paint, there is nothing. Random uncontrolled use of paint doesn't make a thing art like Virgen of the Rocks is art any more than banging randomly on a keyboard makes it music in the same category of  music like Beethoven's Moonlight Sonata, so, the Pollock piece isn't art.