Yea, I pretty much take the retcons Fallout 3 implemented with a grain of salt.
These were people who got to play with the toys from someone else because they had the money to pay for them, not because the original designers thought these were worthy successors to continue their creation.
Kind of like if for example a fantasy writer of today somehow managed to buy the rights to Tolkien's books and then continues the saga by writing books that take place before or after The Lord of the Rings like for example Frodo and Gandalf coming back to Middle Earth to warn the human kingdoms that Sauron has managed to survive and now has freed Morgoth and they are now creating an army of new balrogs by using genetic material from the balrog Gandalf defeated.
And Saruman is actually a time traveler from the future who went back in time to change history when he felt that future Earth was to overpopulated by humans.
But now Frodo, Gandalf and Aragorn need to go into the future to recruit a younger Saruman who knows how to defeat the new balrog army, only to reveal that these balrogs are actually the original army Morgoth had under his command in the beginning, thus they need to be send back in time to close the loop and prevent a paradox.