You know this sort of reminds me of Mass Effect 3 and the whole argument about how dilogue options (particularly of the neutral sort) were excised in that title. To me it's obvious things like skill checks and the more quirky dialogue options in FO4 were set aside due to the inclusion of a spoken word protagonist. This is the price to be paid of hearing your character speak and I imagine it will be like this from now on - I mean what are the chances of Bethesda going back to the old system for TES VI, for example? At some point, there must have been an understanding that the general gaming public would respond better to hearing their character recite their lines than to the inclusion of multiple dialogue options and branching conversastions. I can't say how accurate that conclusion is, as I don't care either way, but I have no doubt the calculus was done and this path was deemed to be the most beneficial from an economic standpoint. Bethesda always seems to be looking to broaden their fan base and they don't seem to worry too much about losing some of the old guard in the process. From what I can see of the extant sales figures, these changes don't seem to have had a negative impact.
All that said, I do wonder how much of the detail and depth of a title must necessarily be lost to continue to "grow the fan base." I'm not sure how many people who play FO4 are really of the dreaded "casual" mold but one must wonder when the blood letting will stop. Although I don't feel this design choice is the most representative of this trend (for reasons noted above), it does add to the perception that Bethesda is willing to sacrifice almost anything in order to appeal to the absolute broadest base possible. I do believe there is a risk inherent to that strategy; in that, if you "streamline" enough, you might very well end up hollowing out your product to the point that it begins to lose its identity. That is to say, you may make another $200 million in units sold but your game might bear little to no resemblence (beyond a cosmetic veneer) to its ostensible genre and historic predecessors. Somehow there has to be a balance between art and economics in this sort of business, I'm just not sure if Bethesda realizes this yet.