Sorry for the delay had to find time to watch these and thanks man this was quite interesting.
Being a developer i knew wasn't easy but i do feel for this guy and he's probably not alone. Vram 'doesn't' really need to be at a certain point, i mean 8GB could be fine but due to time constraints and budgeting i can see where he's coming from. If only targeted systems had more vram to work with it could save a lot of time and that would also improve personal well being as well. So one hand you're waiting for the public to catch up in system specs and same time have the company you work for screaming deadlines at you. Quote from the dude,"There's only so much we can do with so little time we have", that's the crazy corporate world we live in huh.
It looks like we're getting there though, not so sure it'll happen within 3~5 years though but it might. The things they want to do, different textures for a whole range of objects. Different rocks or grass, nothing is ever the same. U5 dev reckons 16 to 20Gb vram for something like that in 1080p med, i dunno man, i think maybe even 20gb might not be enough for an avg size open world game with that kind of detail and that's only in 1080p lol. Direct storage might help with that but as said there it's not a silver bullet but it could help.
No, DirectStorage will not help. What DirectStorage does is making direct streaming assets from storage to GPU possible without the need of CPU.
Normally, a PC cannot transfer assets from storage to VRAM directly. It has to go to DRAM first, then to VRAM. So, if the game needs 16GB of data, 16GB worth of data has to go to DRAM, first, then to VRAM. That is why you need some crazy amount of DRAM like 24GB or 32GB. 12-20GB of it is "reserved" for graphical assets of the game. The DRAM acts as a "temporary storage buffer" for the assets, because:
1. Streaming data from storage to GPU directly isn't possible
2. The storage speed is too slow to reliably stream assets
3. The GPU does not have enough VRAM to store all of the assets at once, so some kind of smart asset switching algorithm needs to be implemented
DirectStorage only solves #1. It does not solve #2, meaning you still need a 3000MB/s consistent read speed SSD. It does not solve #3, meaning that you still need a GPU with VRAM that is as much or more than the consoles' RAM.
Don't get me wrong, DirectStorage helps tremendously. The processing unit that moves the assets from storage to DRAM, then to VRAM is CPU. The one that decompresses the assets is also CPU. That's a lot of work. This might be shocking, but the CPU is not that powerful, especially compared to the GPU. Go find TFLOPs of a CPU, it is not that high.
What DirectStorage does is use the GPU to decompress the assets instead of the CPU.
That said, if what Nvidia said about RTX I/O is true, and it works as intended, THAT can help in reducing the amount of VRAM GPUs need to have.