I think the idea itself is cool, but - as was already stated before - it's been "proven" by a lot of other games that it can be a real pain in the a cause NPC gets stuck somewhere,
causing the quest to fail without you making a mistake...just annoying waste of time then, and very frustrating.
Problem is: You can't for example just copy the AI of the drone (which also is supposed to follow you)...beacuse when this one gets stuck somewhere, it will (as was said) just teleport back to you when you get too far away.
In that case it's necessary to avoid silly "micro-management" to get your drone free, and - if not happening too often - is a simple workaround, especially in a fully destructible world, where paths are often blocked/destroyed/created new,...
But imagine that in such a rescue mission...you could easily cheese those quests by just shortcutting straight through the next best wall to the destination point, and your NPC keeps teleporting after you.
Nope, wouldn't be fun that way...and otherwise, that guy would just keep being stuck behind walls, edges, stairways, doors, chokepoints, fall through holes,...of my,
I'm getting angry just by thinking about it
So again, cool idea, but the effort to get it straight in a fully destructible world is...just wow.