If Bethesda ever did this, which I doubt they would, I would prefer it if the long standing engine bugs be fixed, as well as all of the known in-game bugs, otherwise I wouldn't pay for a re-mastered version at all (Because it shows Bethesa doing minimal effort for a quick buck if they don't).
It was a lot easier to do this with Halo because they just had to redesign mostly linear levels and a small amount of unvaried NPCs. Doing this with a large RPG like Fallout where they'd have to redesign a massive landscape in addition to hundreds of individual NPCs would be a difficult task I would think. But I would enjoy a remaster and cheap bundle similar to the Master Chief Collection if they were willing to put in that time and effort. There's always the question of whether you should buy a game you already paid for again just to see better graphics though. To be honest, I think it would probably be best to just look forward to the graphics of the next game, as all the content will be refreshing as well as the graphics.
EDIT: Unless you just mean take it as it is and put it on the current gens. I wouldn't see much point to that and the end of my post would still be the same.