It is actually a resource thing. It depends on how many people, how much time, how talented, money, etc.
As to your second point, I don't think it's true that other AAA games aren't doing this(don't know if that was what you meant).
I would argue that RDR2 and Naughty Dog games are there in terms of putting this amount of care and detail into their environments, but Naughty Dog does it very linearly and Rockstar has lower quality in terms of rendering of objects up-close.
Star Citizen is trying to do both, but at the same time not doing it better than those two as a consequence.
Yeah, but at the same time, you made it sound like the talent they already had, was worth next to nothing, as well as the tech and resources put behind it, because you basically compared it to current gen games, and made it out like next gen games are somehow going to "easily" surpass what SC is trying to do (entirely based around said hw specs of next gen systems, but we've all been down this road before with current gen, and last gen even).
I think it is, because you see a nice vista in RDR2, I see an empty world with a few NPC's attached to a few nodes, that activate whenever you enter a vicinity. There are still invisible walls or areas that prevent you from transverse hundreds of miles, while in a game like SC it's so much more bigger than what we've had in all the AAA games we've had this gen alone. It comes with worlds that contain much more land that your average Battlefield map, or RDR2 even, and yes, they are doing some generated content, as well as hand crafted to go along with it, which is better than the usual typical places we see in worlds like RDR1/2 and GTA/Witcher and typical RPG's.
I don't really see the others as being on their level, not in terms of raw visual fidelity and animations for multiple objects, physics and all sorts of other actions you can do within that game. R* has a terrible moniker for not rendering details and objects as far as 3-5 meters, shadows and all, which is just not acceptable. They also have some of the worst AI I've seen, hell most AAA's do these days, in terms of actual intelligence.
SC is doing what the other two are not. It's trying to make a fleshed out SP game, as well as an open world galaxy for people to make their way in. Amounting it to nothing, because it's not copying ND, or R* is honestly narrow minded, and I'd really hope they never follow your viewpoint on how games should be made.
I want to see vast worlds, filled with actual meaning and purpose to them, not "hand crafted" vistas, where I cannot interact with each leaf, or vine, let alone destroy a part of it, or even travel towards it in the distance. We've seen so much of that this gen, that it's left me with a hallow feeling when it comes to AAA games, because most of the time it's just one big fancy looking prop, with very little meaning behind it.
I actually want AI to vastly improve next gen, tenfold even, and I honestly don't care if it's not "following" ND or R*, because those two are not the godlike masters of everything either, and they have a lot to improve upon themselves.