Right now, many Wear OS 3 apps don’t support on-display/ambient mode. Google has released a new update of its Google Maps for Wear OS 3 and Pixel Watch, in which Google has enabled AOD. The previous UI showed a map and swiping up for that list to access turn-by-turn directions.
After this update, there is now a dedicated list view that takes up the entire screen. No map appears at the top until you switch to that view by tapping the new pill-shaped button at the bottom (as seen at the bottom left). In Map view, tap the arrow button to return to the list.
The map or list will remain active even if you put your wrist down. The new update version 11.65 of Google Maps has already been launched but the features are being released through server-side updates.