I'm playing Fallout 4 at the moment and having a lot of fun and I say that as someone who not only loves the original 2 but replayed them at the start of the year, so they're fresh in my memory. ¯\_(ツ)_/¯
I find it honestly pretty odd that you cut Fallout 3 some slack but are hard on 4 even though 4 is pretty much better than 3 in every way, the color palette is more colorful (3 was part of that 7th gen trend of monochrome color palettes) the gunplay is more fun and the writing and storyline, while not up to par with New Vegas, is still a lot better than 3.
And I'm also pretty sick of this trend of bashing modern games for the sake of bashing modern games, I mean the original Fallout is almost 20 years old, Fallout 4 came out last year, of course they're radically different styles of game, what do you expect? that doesn't make 4 bad.
For one thing the art design in Fallout 4 is top notch, almost everything has been redesigned to look like it has more real functionality while still retaining the retro futuristic style, this is most obvious in the Vaults, which is super cool, on top of that I love finding the various stat boosting magazines just to see the art on the covers, Bethesda hired some real talent in the art department for this game.
This kind of comes down to the main difference between current and classic gaming, the original Fallouts like a lot of classic games rely a lot on your imagination, on stuff like music and other subtle details (like the excellent interface design you mention) to create the tone and paint the picture in your mind of the game's world in ways the graphics alone could not, there's nothing wrong with that but there's also something to be said for being thrust into an immersive fully 3D world with the impressive quality of current gen graphics (it's pretty amazing to play one of these Bethesda open world games with graphics of this caliber)
This is not to say 4 bereft of criticisms, but it really irritates me how so many people look at the glass half empty when it comes to modern games, I don't see how someone could not have at least some fun with Fallout 4.