The game being isometric is one of the most integral things in this definition of what makes Fallout, Fallout?.
No. Isometric and FPP presentations are fundamentally opposing. Isometric is better suited to a game about resolving another's situation, where FPP is all about resolving one's own situation. Lore & Setting aside, mechanically the later games seek to put the player in situ, rather than to evaluate the PC's situation. The latter games focus on "...and we're walking, we're walking, in the retro 50's theme park." rather than focusing on the world and the PC's place in it.
These games have polar opposite design goals.
A good case in point: Targeting. In Fallout, the PC always does the best that
they can; the player has no agency in how accurately the PC attacks a target. In FO3 and afterward, the PC has [almost?] no agency in how the player attacks the target.
Is it not? It is a continuation of the stories that the originals told with it's own identity specific to it thrown in, similar to how Fallout 2 has it's own identity that is similar, but also separate to Fallout 1.
No. The sitcom Frasier is a spin-off of Cheers, the sitcoms Maude and The Jeffersons (for example) are a spin-offs of All In The Family... they are not continuations of the story—or even of the format. They are each their own unique beast with their own style, but with familiar ties to each other. They offer something entirely different, based upon something entirely familiar.
[This is what FO3 does; this is what FO4 does—of FO3.]
They are in effect, "If You liked Wasteland, you might like Fallout!".
*That was actually what Fallout did too...
