WSB was heavily pushing the "fight against the injust hedge funds" narrative and the way that community speaks is a pretty big indication that they don't normally align themselves with SJWs.
I guess that is how the term is defined by people who dislike them, but I think the core motivation is social progressivism and generally left leaning politics. SJWs are unlikely to favorably compare themselves to 4chan or use the n-word and r-word. I don't think the heart of WSB is particularly political, but it certainly gives off vibes that are closer to the alt-right than SJWs.