So, I'm late to the party, but... some thoughts.
V's initial, gut objective that occupies their mind is, obviously, 'I don't want to die'. But is that the limit of what V wants? Early on, we get the convo with Dex about a quiet life or a blaze of glory. We know what Dex chooses, and we know how it works out for him. We also, if we get to the right point with the ending, know what the other choice gets you, and ultimately, it's the same thing: dead.
Because in the end, that where every road leads. We all die. But who are we before that?
The Story
The story is what you make of it. If you just rush through the main chain, skipping time when it tells you 'wait for X to call', then yeah. It's incredibly weak, and there's little to no character growth. News flash: that sounds about right.
Taking that route is the equivalent of going to work every day, clocking in, doing the absolute minimum, clocking out on time, going home, and well... tuning out in front of the TV, or playing video games until it's time to go to bed so you can do it all again the next day. The story ends up weak and un-compelling because that's the Story of V that you chose to write.
Add in the side-quests—not all of them, necessarily, but the ones involving Johnny and the personal relationships you make over the game, like Claire, or your romantic interest (whichever one you have available), or even Jackie's funeral (if you sent him home to Mama Welles)—and that's where the personal growth comes in. The moments. Even moreso if you just explore the odds-and-ends within your own UI. Leaving messages on Jackie's phone as a way to hold on to him or as a way to say goodbye... that was a nice touch they put in. And while the choices you make in those side-missions don't necessarily change the dialog options you're offered at the end... they might change the options you pick.
Voilà! Character growth.
Agency
One of the big evils in cyberpunk (the genre, not just this game or even it's awesome predecessor from R.Talsorian) is a lack of agency. Everyone's basically stuck in place. Everyone. The wageslaves, the street trash, mercs, even the most powerful megacorp executives. And that's here. We see that. Even the Arasaka family, in the end, can't escape being locked in place. Saburo wants nothing more than the status quo. Hanaka sees no greater purpose than the dutiful execution of her pre-ordained role. Yori's whole story is the guy who tried to escape his family, but eventually gets dragged back in—potentially to the point of having his brain turned to goo in order to reconstitute dear ol' dad, or takes dad's place to become exactly what he didn't want to become. In the end, they're all helpless to change their lot in life.
That's the lesson here. That's the story—the real one—in Cyberpunk 2077. V starts off demanding 'what do I do, Vik?' and looking for people who can answer that question, tell them what to do about it. And it's completely possible to get through the whole story still asking that question. That's the question that leads to either letting Johnny and Rogue do it for you, or letting Hanaka Arasaka set the agenda.
And both of those cost you everything, in different ways. Instead, the 'right' answer is the one Vik's been telling you all along. It's the one Jackie chose: bet on yourself. Take matters into your own hands. You go, with the people you've developed relationships with, who trust you. The people who aren't there for the corp, or for Johnny. They're doing it for you, because everything you've done for them means you're family to them now.
And that gives you the 'happy' ending: V ends up with their romantic interest, riding off into the sunset. You get the boy/girl because you made the choice to take charge of your own fate.
But V Still Dies!
Yeah, even in the 'happy' ending, V's still got six months to live. And? Unless the game zips ahead to show you V and their partner growing old together, the ending is as happy and defined as any other 'riding into the sunset' ending. For all we know, after the end of The Princess Bride, Westley and Buttercup suffered PTSD for years, made one another's lives miserable, and finally died in a house fire after a mishap with an oil lamp.
Let's say V gets cured. Survives. They're still living in an unforgiving hellscape of a world where damn near everyone is sizing them up as potentially either a victim or a mark. Hell, they could get hit by a truck crossing the street. Or tagged by a stray bullet.
This is Night City, and 64 years after the original Cyberpunk, it has only gotten more lethal and more completely arbitrary in its lethality. Five minutes after any credits roll, V could be dead. In the 'happy' ending we get, V's going off with the Aldecaldos to make a new start. They've got the person they love with them. They're happy, and they're hopeful. And in a world like that, that's an incredible thing.
But that's Fake V! V's Soul Got Killed!
Ok, look... the human mind is a construct of the meat. It's an emergent property of the electrochemical state changes of the brain over time. So yeah. Did V die when they got hit by Soulkiller? Sure, why not? The person who wakes up... is still V. Technically a different V, maybe, but for all intents and purposes, that's V. Is it a little creepy if you think about it too much? Uhhhmmmm.... yeah! Yeah, it is. But in the words of every doctor who's been told 'doc, it hurts when I do this'... so don't do that!
Seriously, the only individual who can tell Fake V isn't V is V. And V's dead. Not even Fake V can tell they're not the original V. And let's face it, this is sci-fi. Do you guys get worked up about the Star Trek transporter? Because that rips you into component atoms, converts those to energy, transmits the energy, and then reconstitutes the atoms. It absolutely kills you, and makes a new 'you'.
As for the soul that everyone's worried about in and out of the game... quantify it. We've got no indication that anyone in the CP setting can actually demonstrate the existence of souls any better than we can do IRL. And every religious reference in basically the whole 'punk genre offers the reader/watcher/player/'tever a picture of religions as scams, making pawns of the desperate. So, within context... what soul? There's no way to show that Fake V has 'lost'... anything.
Wrapping It Up
So, yeah... all in all... you get out of the story what you put in, and the Nomad ending really is a happy one. Because it's the road you forged, and you've gotten a result that's a damned sight more than 99.999% of the world can claim, either in-game or RL: you're free, and you're happy, both at the same time.
Enjoy it.
That newly introduced neighbour -- not really.
