This is a good point, but we are talking about our own personal headcannons. It's about what we as fans want to consider canon and not. There's enough in Fallout 3 that's good I want to consider canon. I like Rivet City, but it can't be in the Washington Naval Yard because the Anacostia isn't big enough to accommodate it. I liked everything in Point Lookout and it's referenced in one of my favorite NV mods, Strangers Aborad. I like Augustus Autumn adnJohn Henry Eden, and their power struggles, not as written but as concept. I like Owen Lyons and Protector Casdin.
The only thing I don't like is that I played Fallout: Doomsday for Heart of Iron 2 and in that game, they had the FUSA, the surviving non-Enclave part of the government that controlled a good fourth of the East Coast. I want FUSA. I want America to survive, because the concept of America is bigger than the Enclave.