The engine could pull it off. It's full 3D engine. You could have pillar raised and could lead you to another level area and back.
If we had infinite amount of time and infinite amount of money, yes, it could be pulled off.
But no, the engine is not "full 3D".
As stated above by Stabbey, the AI grid / Pathfinding is 2D. You can't pass under a bridge and above. You can't go on a balcony and pass under it. We also don't have any "moving platform" whatsoever. We don't have the tech for it.
We always block one of the path because the AI grid doesn't handle that.
Have I personally asked to be able to have a 3D grid? Yes. Will it happen? Not for now. It would need a really big amount of work to be done. Switching from 2D to 3D is one hell of a task.
CRPGs are usually pretty static environment wise.
If you look at all the other top down CRPGs, DoS is pretty much the most dynamic. Could it be more dynamic, for sure, no doubt about that. But everything has "a price". When you make a game, you have to make choice. You can't ship all the ideas that you have if you want the game production to not last forever

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