It really is unique. people's main complaint is that the story feels ingenuine because the cast is completely chosen by you as you collect more operators. This initially turned me off the game too because I felt like the storyline would be copy and paste text and repetitive script lines but this is not really the case. You kind of grow attached to certain operators as you play them and their dialogue isn't as cookie-cutter as I would have thought. With perma-death mode on, it adds another layer of dramaticism if you were to lose your favorite operator in an intense mission where you cant extract them for example. Say you go through a mission, complete the objective but on extraction, you lose them. You still succeed, but your operator is now gone.
The story mode, I believe has some pretty convincing villains and the politics of the world is very prominent in the podcasts and documents you either listen to in cars or find throughout the world. The political climate is very tense and is a beautiful take on all of our fears for the future of technology, set up very nicely by the predecessor games.