I actually think Fallout 4 is probably better than Fallout 3. It's barely an RPG, but it's a thoroughly competent action open worlder. Fallout 4 is a game that if you take it on it's own terms is good at what it wants to be
Fallout 3 is kind of a mess. It's trying harder to be an RPG, but it's not succeeding, and I just find it a lot less fun to play