Oliver starts talking at ~5m20s. He also hints at Sampler Feedback Streaming not being used because it's too costly to implement, and some other features not being implemented by engines because Sony doesn't support them.
It's interesting how 4 years ago "VRS Tier 2" was hailed as a tech that would claim ridiculous performance gains, just to get sidelined to software solutions that ran on the GPU's shader units with better results.