I had a thought yesterday.
Writing a novel is like composing a symphony.
A session of an RPG is like a jam session.
The two are very different art forms. I think about this a fair bit because I have sometimes found that if I'm roleplaying with somebody and tell them I'm a writer, they suddenly start expecting perfection from every post or statement.
Most novels are edited multiple times, often by multiple people. They're set aside, come back to, reworked. Obviously if I'm saying what my character is doing in an RPG - I'm doing it off the cuff in five seconds.
It's improv. There's no rehearsal. And that's what makes it special - creating a storyline with others more or less off the cuff.
But please don't compare the two things. If you're privileged enough to game with a writer, understand that what you're doing is the equivalent of grabbing random instruments and a corner of the bar and just going for it.