The most likely explanation is that this was taken over the night side of Earth, not in full daylight. The bright band is atmospheric glow/airglow, and the surface/Cloud detail can still be visible when lit indirectly by the Moon, much like landscapes in night photos or the Moon’s dark side lit by Earthshine.

That means the scene’s brightness range is far smaller than “sunlit Earth plus stars,” so a single exposure can capture both. The stars are bright point sources, while the Earth in this image is not being illuminated by direct sunlight. That’s why it doesn’t blow out the way a sunlit Earth would.

So this is less about huge advances in dynamic range and more about the actual lighting conditions. If Earth were sunlit, exposing for stars would normally overexpose it badly. But with moonlit night-side Earth plus atmospheric glow, the brightness relationship is much more manageable in one exposure.