I agree. Skyrim's primary storylines actually trailed you through a lot of the landmarks. There was far more opportunity to go, "While I'm in the area doing this main quest, I'll take a look around." As opposed to there being huge sections of the map that were never even used as part of the primary quests. You rarely had the reason to ask yourself, "why does this area exist? there's nothing here but sidequests".
How far have you actually played into DAI yet? Just curious for purposes of further adding to the discussion.
While I am not in a position to actively talk about Skyrim in it's entirety, this is because for me - Skyrim was a vast open waste of time and boredom. I recognize that the game is beautiful, huge and for a sandbox person/mod-happy player? Amazing. But I simply found it a boring trek for hours poking at various areas going "Eh" combined with what I found to be a snooze-worthy combat system. But, that's neither here nor there for DAI discussion. Even in saying all that, again - much respect for Skyrim for what it is, just not my cup of tea.
But to the point about DAI's side quest zones being basically a waste of space for side quests - have you actually COMPLETED these zones?
Emprise du Lion. Emerald Graves. Exalted Plains. Each of these zones, while not having a "main" plot quest in them, has a large story thread that still ties into main story events - further, you note that Skyrim guided you around so you could do things as you went for big objectives. DAI is not much different here - the people clamoring that "OMG it's just an endless land of picking flowers, etc." when this is patently false.
I recently completed Emerald Graves - in it, I found several quest threads with large relevance to events that pertain to the main plot - while they do not affect it, they certainly stood out as something that would merit attention and time from the Inquisition to investigate and solve. In the course of these objectives, as I moved through the map pursuing these goals and helping people, I collected shards, purged rifts and when I FELT like it, gathered some crafting materials.
This whole "Gotta pick everything as I go!" or "Focus only on the menial tasks!" mentality is damaging to your game experience. Why would you do that? You wouldn't do that IRL - you'd multi-task and the game arranges this pretty well. I look at my quest object - ok, around this, there's 2 shards I can grab quickly working towards my goal of understanding and unlocking the Temple in Oasis...and I also happened to gather a few nodes of metal that will help my crafting. Excellent - now to focus on the actual objective. No time wasted. No massive tedium. One area of Emerald Graves cleaned and finished and on to the next quest portion...
While I understand the way I do this may not be how someone else does it, the point stands - these zones are not simply giant wastes of space. There is relevance and flow to them and I respectfully submit that if people are going in and only going "God, I gotta comb this zone for ALL THE FLOWER THINGS" without focusing on the relevant quests and gathering around that, you're making it less fun on yourself in the end.