Sure, Fallout 4 gives you a bit more of a background, but is it REALLY such a big deal that you had a family?
Depends how much of a role it plays in the game I would say. How tight the narrative will be to this
pre-war-amercian-dream-family-man fantasy that Beth has probably built around your character. If it's just serving as some sort of cleverly done tutorial? Probably not more than in any other Fallout game where you really don't have to worry to much about your background. But if it actually serves also to set the tone of the game from the start? Closer to what you have with The Witcher 1 or Mass Effect? Than it would be quite a deal I would say. If for what ever reason most of your options in the game like with the dialog will one way or another be focused around your characters
boohooo-I-lost-my-family complex.
For example no matter how hard you try, but in The Witcher or Mass Effect your actions and dialog options will always reflect your work as professional monster slayer and beeing this
me-shepard-save-galaxy-now thing. It still gives you room for different outcomes, like helping team a or team b etc. But at the end of the day, no matter if you're chosing to fight or to negotiate, you're doing it within the predefined tone of the game. This isn't what Fallout was about - nor what it should be about. Your background didn't dictate your choices. If you wanted to play psychopath, you could do just that. If you wanted to play a diplomath, you could just do that. If you wanted to be evil. Just go and be it! And in many parts, this was reflected by the dialog and skill/stat checks. The Witcher really doesn't allow you be a civilian killing psycho for example. And in ME pretty much all decisions have been about doing good things as good guy or doing good things and beeing an asshole about it.
We have to wait and see how much of that character freedom will be in F4. But I doubt it will contain much of it. My guess, and that's just pure speculation, is that a lot of the focus and resources in production was throw in to the post-apocalyptic minecraft experience where everything else like the story and character choices is just subsidiary and more like an afterthought, because things like story and dialog is simply something that an RPG must have, somewhere.
It would explain a lot in hindsight. For example why they have almost shown nothing from the dialog in the game - nothing that is really telling us what kind of game we can expect. Will we have most of the time 2 or 3 answers that lead all to the same result? Or will the game always be limited to this A - B - C -D thing? Or will we have more options than that? Or showing us zero parts from the story-direction. Not even hints. Like explaining a bit about the factions, hell for now we don't even know if there will be any - albeit I would say that is pretty much a given. And why they are somewhat reserved with showing more of the perks in action while a lot of the focus in the media and advertising was spend with their minecraft gimick of building your own post-apoc village and power armor.
I am curious what the explanation will be for that anyway. Just for the lulz? Or maybe because your character has this deep emotional need to recreate his hold american-dream that he lost with the bombs? We will see I guess.