https://www.pcgamer.com/assassins-creed-odysseys-exploration-mode-culls-the-map-markers/

Assassin’s Creed typically flings map markers and icons at players. Unity was a particularly egregious example, with the map of Paris nearly invisible underneath the shroud of diversions. Ubisoft managed to rein it in a bit for Syndicate and Origins, but in Odyssey a different approach is being taken with its new exploration mode. 

Odyssey features two ways to play the game. Guided mode is the more traditional of the pair; it doles out map markers and quest objectives so you always know what you can do and where you have to go. The new mode, exploration mode, seems to get rid of all that clutter; as the name suggests, assassination targets and quest objectives must first be discovered via exploration. This, says Ubisoft, is the way the game was meant to be experienced.