Many in the New Age movement deny the existence of real evil. Some go so far as to deny any real existence at all and imagine that this is all a dream or illusion. Maybe it is an illusion, or based on the principle of illusion, nevertheless pain still hurts even if it as illusion.
“Evil” can refer to “suffering, misfortune, and wrongdoing; something that brings sorrow, distress, or calamity.” Merriam-Webster
Even if it is ultimately an illusion, there is apparently a lot of suffering, misfortune, and wrongdoing going on in this world every day. Is it necessary? Could it serve any purpose?
The answer depends on how you view the universe.