Question

what is not true of all antagonists?

Answer 1

Many things are not true of all antagonists.

The conflict of the plot is called the AGON. Usually there are two parties to the conflict: the protAGONist and the antAGONist. The protagonist usually is the main character or hero. The antagonist may be a really evil person. But sometimes the antagonist is nature or a bad aspect of the protagonist's character.

So you might have: man versus nature (a survival story), man versus drug addiction, and so forth. Even when the antagonist is a person, he or she might not be really evil, but only is someone with a competing interest in the conflict. So you may have man versus noble competitor.