>>353623341
My guess would be lower settings, dynamic foveated rendering, and maybe a lower render scale. It's not like everything runs at native resolution on the Quest, so I'd expect similar tricks on a Valve standalone. I'd also assume it'll be running something at least a little stronger than the Steam Deck APU by the time it actually releases since it's only a rumor at this point.
The benchmarks were just to show that the prerelease Steam Deck hardware isn't as weak as you were saying. Considering what they've already said about trying to use the Steam Deck for VR stuff, I couldn't see them using the same hardware in a standalone headset.