They spent about 20 minutes discussing. You could of timestamped the video
From listening, it's broken down to a few things.
1. Developers will have to work harder and utilize features like the SSD, especially on the Series S as this gen progresses. They'll be more intelligence in the use of the hardware.
2. Unreal Engine 5 can run on Series S, but probably not at 60fps. You'll probably end up seeing more 30-40fps games on Series S going forward.
3. You'll probably also see less 1440p games on Series S, probably sub 1080p as games become more demanding.