Well, I think I may understand you in terms of immersion, and even agree with you. However, in terms of gameplay, depending on how the quests are located, having to do them one by one, specially if one quest means going to several places, may be a horrid pain in the ass. And anyway, it would be only an option, so the player can track quests one by one if he chooses so.
F***k, even in terms of immersion, you are Geralt, you speak with a shop owner in Nolfgaard who wants an ingredient, a friend who asks you to kill a guy there, a merchant who wants you to kill a monster, and a couple of other people who give you objectives there. If you were Geralt, would you go to Nolfgaard, kill the monster, come back for the reward, then go there again, find the herbs, come back, go there again to kill the guy... and so on? No way. You would just remember by heart what you would have to do there, do everything, and then come back when it's convenient.
I do care a lot about immersion too, but it's a game, for God's sake. And playing TW 2 is being cumbersome for me because of several gameplay flaws, not because they didn't do a good story or the graphics were not good enough.
A good example of good RPG design without many markers is Divinity OS, where direction indicators and clues replace in many cases a lot of arrows, which is good and immersive. But it's also a game where they give you objectives that are close by, no need to exit a village and walk through the forest back and forth 3-4 times.