Long-form can avoid this problem, because to put together a cohesive piece, you have to do a little reflection and possibly research. Plus, it is considerably higher investment on the part of the author, so if it has been said before, they'll be more likely to write about something else.
"possibly" research? Sorry, but the attitude that research -- i.e. the consideration of history and the big picture -- might "possibly" be a part of longform writing is like saying math might be a part of good physics theories
I see where you are coming from, but some long-form writing is itself the research. Paul Graham (IIRC) said that his essays were a way of exploring ideas. In some of my writing, I have this to be the case also. And then, of course, there are writings where the actual banging words out is a tiny sliver of the total time taken, when compared to the research component.
