That's likely as much a limitation of the art pipeline (it's expensive creating high quality assets including model, textures, and animation) as it is the hardware. And nothing precludes X version of the game having fewer NPC's than Y version of the game.
Being the same game is what precludes versions from having different quantities and varieties of enemies. Rendering resolution, polygon count, and animation quality don't mechanically change a game. Differing enemy types and quantities does.
There were PSP spin offs of PS3 games, and those spin offs were of such poor quality that they could barely be said to have any connection to the originals that spawned them. How many Wii versions of PS360 games required entirely separate teams and resulted in almost entirely different games?
The art pipeline plays some role in overall enemy variety, but the cost of most aspects of each enemy type is fixed, so the variety of enemy types in each combat encounter is a limitation of the hardware at higher-than-PS3 levels of presentation.
Reskins of the same enemy can share animations, sound files, polygon meshes etc. There's a small additional budget for reskins. Even discounting the IO subsystem, an extra 8GB's of memory is a substantial amount for greater variety. That additional 8GB is now virtually guaranteed to be used for extra lipstick.
This wasn't a hardware limitation as in the hardware wasn't capable of it. This was a limitation of the level of art or presentation that they wanted in the game limiting what they could then do with the game.
The hardware wasn't capable of it and still isn't at a level appropriate to the generation. You could fly the dodo in GTA3. No-one would accept a sudden drop to PS2 quality assets in HZD, and flying wouldn't feel like flying if you're moving like a feather being nudged along by a field mouse's fart.
This was a limitation of the hardware as well as the public's expectation of what that hardware should deliver. They could include supersonic flight if all textures and sound was suddenly stripped from the game. That doesn't make it a viable solution in the overall aesthetic.
But what is viable is that the flight in Horizon FW will be limited by the PS4's capabilities (bearing in mind that they aren't going to drop asset quality to ~Wii levels) and the PS5 will be used to slap on some tits and a wig.
The same applies to number of NPCs. The game could have had more NPCs (use the art budget to create more, but less detailed NPCs which consequently is less taxing on the hardware).
Sure, they could have infinite variety by reducing all enemy types to stick figures. But there's a limit and a balance. The NPC's you encounter are already relatively low quality compared to Aloy. How far can they go before there's a noticeable, generational disconnect between Aloy and those around her? As I've already pointed out above, reskins can share a lot of assets. Entirely different mechanical types cannot.
The fact that the recent PS5 gameplay reveal showed us a PS4 level of per encounter enemy variety backs this up. The PS5 version is mechanically limited by the PS4. Aesthetically, less so.
They could have easily included flight (but at increased development time cost and some nebulous decrease in art/presentation quality elsewhere in the game).
Easily? They could have easily included a form of flight that moves at the maximum galloping speed of a mount. And unless there's a substantial downgrade from Horizon ZD to the PS4 version of Horizon FW, that's what we can expect on the PS5 too. But with a fancier coat of paint.
The proof of the pudding is in the eating, and the behind-closed-doors demonstration of a massively increased swinging speed in Spider-Man is clear evidence that movement speed is limited by IO. Now, moving at speeds imperceptible to anyone other than fighter pilots isn't saleable. But moving at speeds greater than an old lady pushing a shopping trolley while also seeing a generational improvement in asset density is.
I always find it laughable that people think flying was a hardware limitation of the PS4 in the game and not a conscious decision by the developers that flying just wasn't as important to them as having graphics/presentation be at X level that they wanted. Sure at X level of graphics/presentation, flying was an extra burden that they didn't want because they didn't want to reduce the presentation. But the hardware was fully capable of flight in that game had it been important enough for them to want to include it.
True. And now they've established their level of presentation. So for the PS4, they either substantially lower graphical quality when flying, or they limit flight speed to ensure asset quality remains comparable to the previous game.
I mean Ark Survival Evolved is an open world game with dinosaurs ... and it has flight ... on the PS4. Granted, it runs like ass with a not well optimized engine, but it's also a MUCH smaller development team (at least when the game released) than what HZD had. Oh and you can build things like buildings and forts ... anywhere you want.
Yes, and worms on the PS1 had fully destructible environments.
[edit] Oh and reading, Manux's post. At least HZ: FW went from flying was impossible to do on PS4 (HZD) because of hardware limitations to now somehow limited flying (gliding) is possible on PS4 because ... PS4 unlocked their hidden GPU? CPU? Secret Sauce? Or they just felt it was important enough that they now want to include it in the game.
No, it's because the gliding we've seen is slower than the horse-like mount or the ziplines from Horizon ZD. There's no magic going on here: a certain amount of data can be streamed from storage per second. If you're on the ground, and therefore limited in the axes along which you can move, that makes streaming prediction easier. When seeking equal graphical fidelity, and limited by the rate at which you can stream data, the speed at which you can move along fewer axes will always be greater than the speed at which you can move along more axes.
So either flight speed will differ between generational versions (meaning missions will be missing from the PS4 or flight won't factor into missions) or the PS5 will see solely graphical improvements.
All in all, I think you're being so reductive with your take on evolution and innovation that you probably shouldn't bother with any games invented after ~4500BC. "Pfft, it's just a differently sized ball and goal." "Tsk, yet another scoring system that could've been accomplished just fine by base 12." "Why do I need to see more than a single boob, ever? I can extrapolate infinite boobs from that one." "Come on now, why would anyone need opposable thumbs when we already have wrists?"
