Eh, they both follow the "your village asks you to look for a thingy, which you then proceed to ask the townspeople about constantly and moving on to the next location, and then springs up a bigger threat, not only to your home but also to the world at large". It uses many of the same plot devices, it's just that FO2 has a ton more side locations because it's just a bigger game. FO1 can be completed with all quests and everything to see in like 8 hours, FO2 would take a bit longer.
It's really more that there's a lot more sideplots and politics between NCR, New Reno, Vault City, and their various spheres of influence, so by the time you're done solving all of their problems you might find yourself forgetting to push for the MacGuffin, IMO. There's a ton of Yojimbo-style mafia action to be had in New Reno between becoming a boxing champion and doing adult movies, can't rush the main quest in such a case. It helps that FO2 has no time limit whatsoever, just an occasional shaman jumpscare.