You have no logic behind it though, not getting on you, but how would it work at all? Like others have said, the 2 games aren't even related, how would you be rewarded for your progress from fallout 3? Really think about it before posting a thread of it.
i think he means like something to the players of old fallouts, like an easter egg or unique item, not overpowered alien blaster or anything, but kind of like how harold appeared in fo1, 2, and 3 (why bethesda, whyyy did you have to stick him to the ground). or in gears of war how carmine appears in both gears...and dies each time (hes going to be in the third one but he might live...or die again, their voting on it). i think itd be a good idea, and it doesnt perfectly have to fit the lore, kind of like how we can get a vault 13 outfit if we preorder from gamestop