If by demo you mean the older Electron version that's been out a number of years now, that's not a demo but rather the same game on an older engine. It doesn't have some of the new features likes maps, player perks, or cursed artifacts. There's a more complete list of what features are new in the 2023 edition on the Itch and Steam storefront.
If you mean the demo of the newer Unity-engine The Exile of Aphrodisia 2023, it limits the encounter selection down about 30 of the usual 220+ encounters, and the game ends shortly after entering the desert or jungle terrains.