Most gamers have 8GB of VRAM, next those with more and then those with 6GB. The most common GPU is the
NVIDIA GeForce RTX 3060. source
nVidia basically control most of the market. Jon Peddie Research
source
Why would a developer create a game that most gamers can't run well.
While Nvidia represents a massive part of the PC gaming market, when it comes to a subset of the gaming industry that is able to run modern graphically demanding AAA titles, the console industry is significantly larger. This overall means that virtually all of the development time will be focused on the console hardware.
Meaning with these current games, the developers were squarely focused on specs like the following.
- CPU: 8x Zen 2 Cores at 3.5GHz (variable frequency)
- GPU: 10.28 TFLOPs, 36 CUs at 2.23GHz (variable frequency)
- GPU Architecture: Custom RDNA 2
- Memory/Interface: 16GB GDDR6/256-bit
- Memory Bandwidth: 448GB/s
- Internal Storage: Custom 825GB SSD
- IO Throughput: 5.5GB/s (Raw)
Since all of the hardware is identical, they can optimize in ways that they can't on the PC, for example, if you know exactly how the SSD, performs, then you can tailor exactly how much you are loading into RAM, since you can be confident that as the user interacts with the game, you can be confident that exactly whatever is needed, will be loaded just in time.
On the PC, they need to ensure that if a user starts the game, that their entry level SATA SSD will not lead to issues beyond a level taking a little longer to load.
They also have limits in what they can do, e.g., if they spent millions developing the assets that could take advantage of 448GB/s VRAM speeds, and probably around ~12GB available for the GPU to use, then they aren't going to redo a substantial portion of that development work, thus you are likely to just get then downscaling textures and other cheaper solutions, and if VRAM is lacking, the go-to fix seems to be just not loading any other textures, and simply leaving in their place, blurry placeholders, thus avoiding the massive performance hit that happens if the video card starts to allocate system memory to supplement the VRAM.
While this game seems to be an example of a bad port, typical console ports, it is unlikely that we well see optimization in the way of graphically demanding AAA titles being able to make due with 8GB of VRAM.