First of all, I suppose it's possible it was added in after Fallout 3 came out but Oblivion has the same type of third person view. Just scroll your wheel and it'll zoom out of first person.
And, again, aecause it's part of the Elder Scrolls franchise, and not Fallout or a standalone game. People expect certain things when buying an Elder Scrolls game as opposed to a Fallout game. There are plenty of developers that are able to have multiple franchises that play differently from eachother. Skyrim may be more similar to Fallout 3 in gameplay than other Elder Scrolls games, but that's exactly what makes it a bad Elder Scrolls game for some people.
Morrowind added third person view, and so Oblivion had it too, then Fallout 3 started using 3rd person camera over the shoulder (and 1st person) when Fallout 2 and Fallout Tactics (a failure that is responsible for changing the gameplay mechanics) had camera over the head perspective, and then Skyrim took Fallout's improved third camera over the shoulder.
Skyrim is similar to Oblivion gameplay wise, and Fallout is a game that came in between and was based on Oblivion (while I still miss the old classic, but I wont call it traditional turn base combat system).
The newest Fallout games are a success on their own, and it doesn't matter what games are they similar to (Oblivion) and what not (Fallout 2) and to what extend.
Fallout was a step forwards with mechanics for TES games. It took a part in the process, and people complaining that every game after Morrowind is poop. Morrowind happened the same way Fallout 2 did one - we can play those games, but remaking them would leave make them like Nintendo franchise - run to the ground and without the special feel to each squeal.
You can have you opinion and it's an opinion threat. Title saying Skyrim is the worst is read "I think Skyrim is the worst, do you agree?"