I don't expect it to be realistic, only believable, plausible, and not insulting your intelligence, because a theme park is easier to design than a coherent and credible game world.
That part feels like the most important part to me. Personally, I don't mind the other stuff much. A little lack of consistency and a tad of above-and-beyond levels of randomness tend to stay in acceptable bounds anyways if the writing is already good. Not insulting the intelligence of the player is a pretty stern requirement in an RPG game, either way.
The point is, if their writing gets to the levels of not insulting intelligence, there's the risk of making it too complex and "book-like" to the main playerbase, which is the one that came in with Fallout 4. In which case, it will feel more like Witcher and Dragon Age, which will repel the Call of Duty and casual crowd, which is bad for Bethesda's business.
Every suggestion or good idea needs to go through the filter of "would it appeal to the shooter crowd?" or "would this catch on it popular culture easily?" which is partly why Fallout 4 had so many cats - it appeals to the modern Internet culture of, y'know, cats. And I love cats, but that's not the point.
This means Fallout, for Bethesda, must not go into religion, race or politics, must be light hearted, fast-paced, diverse in tone, action-packed, and must continuously stay relevant in popular culture. It must not have story depth for fear of attacking the pacing or alienating a casual gamer with excessive lore. It must have a lot of features to keep large audiences interested without having to risk making them not buying because they heard it was too hard. It must, above all, convey an open narrative to allow for DLCs and expansions to draw the playerbase back in.
Does this sound like Fallout to you? No? Too bad. This is how it's going to go. But I like to spectate the fruitless attempts at making Fallout something more than a pre-made factory product, so keep on fighting.