basically “the ~out of world reasons for why this happened” (vs. ‘Watsonian,’ which is the in-universe ones)
like, let’s say there’s a TV show, and one of the major actors dies, so they say that the character moved to Canada
the Watsonian reason that character isn’t around anymore is that they moved to Canada, the Doylist reason is that the actor is dead so they obviously can’t have him do anything