So then don't torture students by making them write long essays and waste their valuable time. Make it the task expressing the argument on a back of a napkin. More thought, less time wasted on writing stuff no one ever read properly.
A lot of time writing is a personal endeavor. A way to communicate with yourself rather than others.
It allows you to lay out your chaotic thoughts in a clear way. It's the foundation for critical thinking.
It'll be a very sad world where kids don't atleast practice this skill.