Why is symbolism and expressionism seen as anti realistic movements?

As opposed to Impressionism, in which the emphasis was on the reality of the created paint surface itself, Symbolism was both an artistic and a literary movement that suggested ideas through symbols and emphasized the meaning behind the forms, lines, shapes, and colors. The works of some its proponents exemplify the ending of the tradition of representational art coming from Classical times. Symbolism can also be seen as being at the forefront of modernism, in that it developed new and often abstract means to express psychological truth and the idea that behind the physical world lay a spiritual reality. Symbolists could take the ineffable, such as dreams and visions, and give it form. (got from google

What it's saying is that colored pieces of canvases is a piece of art