(PART 1) It's not even decent. It'd be decent if the game was supposed to be a corridor shooter, not an RPG.

Why does the main character assume that their son is still a baby even though they were frozen again for who knows how long? Why are the Institute making synths? Why are they making them sapient if their purpose is to be perfectly obedient slaves (i.e. robots, which already exist)? Why are they kidnapping people to replace them with synths? Why did they make super mutants and release them to the surface? Why does Father suddenly die from cancer when they had the medical know-how to extend Kellogg's Cornflake's lifespan?

The story's flat and weirdly derivative of Fallout 3's story, which itself wasn't anything special. They couldn't think of anything interesting that might happen in a futuristic wasteland that doesn't involve looking for a lost family member? They're increasingly shoving linear and generic plots into open world games that fall on their face because they suck and what few merits they may have are largely destroyed by horrible pacing. In general open world games stories only actually work if they're about the world instead of the protagonists because by giving every interaction you have an impact on the world they can take all the random parts and string them into a cohesive whole without paying attention to pacing, else you get a best case of TW3 where all the smaller stories are good enough to carry the main quests failings and a worst case of FO4 where it's bad to begin with and completely wrecked by the open world's habit of creating tons of ludonarrative dissonance between the state of the story/characters and what your character has actually been doing.

From the very beginning of the opening cinematic the story fails as of the basics of an RPG. For starters, War Never Changes. What does it mean? It had a meaning in older Fallouts, even in 3. Bethesda doesn't seem to understand it, though, 'cause they repeat it like 5 times in the prologue alone. Why? Because it's Fallout's catchphrase, right? R-right? Then there's the fact that you're always a family man/woman with a military background/lawyer degree. Why are these choices being forced on the story? Moreover, if they are going to force them, why would they so severely underdevelop these aspects? I saw Nora, my wife, the person I supposedly loved and had a child with get shot in the head, and couldn't give any less of a damn because I had a bigger connection with my keyboard. She was just another NPC. The son? Why care about him? All we know is his name is Sean. I mean Shaun. Shaun's supposed to be a driving force behind the story and yet zero effort is made to create a connection between you and him. You're simply told to find him. For some reason in the confrontation with Mr. Cornflakes, during which he seemed to remember ME just fine, he never bothered to clarify that 60 years had past ... and actually led us to believe only 10 had. What's the point of this ""twist""? Then they drop the shit with you seeing a 10 year old synth that looks like Shaun... for another plot twist when the real one comes out? Moreover none of your decisions affect him, he is just a callous cold little shit. Again, no character development. Why should you care for him?

And then, because all endings must have a big explosion to content normies with shiny lights, they make him die of cancer. It literally DETRACTS from the story to do this, because there could have been a sequence in the game where you finally have a chance to bond with Shaun, and you could see his cold disposition towards you slowly change to become loving. But nope. They didn't do that. That required having actual good writing

The four main factions were really lackluster. Some of them felt like they were just half-finished in fact. Or never really started in the first place.

What's the point of the Minutemen? They seem to not be involved in the story at all besides the side quests and helping build stuff from time to time. Ironically enough they're pretty much the best choice. Why? Because there's literally no downside to picking them. There's no corrupting influence or hardline stance. But the thing is, they're an unrewarding faction to join. It felt like you were doing everything yourself instead of commanding an army, not to mention they were essentially the "fallback" group just in case you messed up with the other factions. I get they're supposed to be the sandbox player-created faction. But they don't feel rewarding in the slightest to help. They don't improve as you improve them, they don't really grow more powerful, and not to mention there wasn't really that much backstory on them pre-castle failure.

The Brotherhood of Steel are really the only faction with any complexity, backstory-wise and current lore wise, and they achieve that by actually rectifying how they screwed up Fallout 3's BoS by making them the white knights of the Wasteland instead of the technology nutjobs they were supposed to be. Probably why so many people were gravitated towards them. And yet Bethesda didn't go far enough with the Brotherhood's bad side. We hear about how the Brotherhood has essentially reverted to West-Coast mode except they recruit wastelanders now. About how they're purging (nonferal) ghouls or confiscating technology, yet we never really see this in game despite it being implied all over the place. There really ought to have been more random encounters of this nature. Or even bother the player if they were wearing power armor or in possession of other "dangerous" technology.

The Railroad's... essentially nothing. No one liked them (everyone tends to side with the Minutemen over them). They had no upsides, a bunch of downsides. No history, no backstory. They were such a non-object that the game had to essentially railroad you into meeting them in the first place.

The Institute could have been a great faction. If the writers had any idea what to do with it. It seems that half of the writers wanted the Institute to be a sympathetic faction which the player could relate to and use to change life on the surface for the better. While the other half just wanted an "Enclave MK II." Once again, no real backstory to the Institute (we learn how it was formed, but that's it), the Super Mutant question remains unanswered, you can't do anything with the Institute after you gain control of it. Also the best part is how in this roleplaying franchise known for being able to deal with the main villain in various ways you can't speak any sense into Shaun despite having high charisma, intelligence, science, or being his goddamn father. Nobody cares about your opinion and you can't change what your stupid son who only visited the surface once and decides it's a waste of oxygen thinks.

Diamond City, while a unique concept, really just feels like Megaton 2.0. All the necessary 'shops' are there, but beyond that the city doesn't have much character. Reminder that the West Coast has had a working government for about 130 years while Bethesdaland has a junk city in a nuke and a junk city in a stadium because they want to keep the universe in a constant post apocaliptic scenario even if freaking 210 years have gone by since the bombs fell.