A good definition of art is "a description of what it's like to be human", amirite?

I would say art is what was created for the sake of creating.

So a drawing of landscape is a description of what it's like to be a human, i don't think so

No, it isn't. That tells you functionally nothing about what art is.

An artist has a 6 year old child who also likes to draw
His child drew a horse.

The artist asked, "You drew the horse wrongly."

The child replied, "How did I draw it wrongly?"

The artist said, "Why does the horse have wings?"

The child replied, "Why can't it have wings?"

The artist said, "It isn't a horse if it has wings."

The child replied, "Then why did you call it a horse?"